@Statistics

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@Statistics

@Statistics — Returns statistics about the usage of the VoltDB database.

Synopsis

@Statistics String component, Integer delta-flag

Description

The @Statistics system procedure returns information about the VoltDB database. The first argument, component, specifies what aspect of VoltDB to return statistics about. The second argument, delta-flag, specifies whether statistics are reported from when the database started or since the last call to @Statistics where the flag was set.

Some components report statistics at the moment, collected when you make the procedure call. While other components report statistics over time. For cumulative components, if the delta flag is set to zero, the system procedure returns statistics since the database started. If the delta flag is non-zero, the system procedure returns statistics for the interval since the last time @Statistics was called with a non-zero flag. (If @Statistics has not been called with a non-zero flag before, the first call with the flag set returns statistics since startup.) The statistics that are affected by the delta flag are DRCONFLICTS, EXPORT, GC, IDLETIME, IMPORT, INITIATOR, IOSTATS, PLANNER, and the compound procedure and stored procedure statistics (COMPOUNDPROC, COMPOUNDPROCSUMMARY, PROCEDURE, PROCEDUREDETAIL, PROCEDUREINPUT, PROCEDUREOUTPUT, and PROCEDUREPROFILE).

VoltDB maintains separate statistics for each selector. As a result, when making two calls to @Statistics with a given selector and the delta flag set, the second call returns results since the first call, even if there was another call to @Statistics with a different selector in between. The one exception to this rule is the procedure statistics, where there is a single set of statistics maintained for all of the procedure selectors. Calling @Statistics with any of the procedure selectors resets the delta values for all of the procedure selectors.

Note that in a cluster with K-safety, if a node fails, the statistics reported by this procedure are reset to zero for the node when it rejoins the cluster.

The following are the allowable values of component:

"CLOCKSKEW"

Returns information about clock skew (that is, the difference in system clock time) between the nodes of the cluster. Note that the calculation of clock skew can be affected by other system activity, such as database transactions and Java garbage collection. This information should be considered only an approximation on heavily loaded servers.

"COMMANDLOG"

Returns information about the progress of command logging, including the number of segment files in use and the amount of command log data waiting to be written to disk.

"COMPACTION"

Returns information about the performance of periodic defragmentation of persistent memory used for storing tuple data. See the section on "How the Database Manages Memory" in the Volt Guide to Performance and Customization for more information on memory compaction.

"COMPOUNDPROC"

Returns information about the performance of compound procedures, per host per procedure. The information includes the names of the procedure and host, the number of invocations, and selected performance information on minimum, maximum, and average elapsed time.

"COMPOUNDPROCCALLS"

Returns information about which stored procedures the compound procedures invoke and how often.

"COMPOUNDPROC​SUMMARY"

Returns a rollup of information about the performance of each compound procedure across all of the hosts. This is the same information provided by the COMPOUNDPROC selector, except aggregated per compound procedure.

"CPU"

Returns information about the amount of CPU used by each VoltDB server process. CPU usage is returned as a number between 0 and 100 representing the amount of CPU used by the VoltDB process out of the total CPU available for that server.

"DRCONFLICTS"

Returns information about the type and number of XDCR conflicts occurring on the cluster. This information is available only if the database is licensed for and operating as an active XDCR database.

"DRCONSUMER"

Returns information about the status of database replication on a DR consumer, including the status and data replication rate of each partition. This information is available only if the database is licensed for database replication and operating as a passive DR replica or an active XDCR database.

"DRPRODUCER"

Returns information about the status of database replication on a producer database, including how much data is waiting to be sent to the consumer. This information is available only if the database is licensed for database replication and is operating as a passive master or an active XDCR database.

"DRROLE"

Returns information about the current state of database replication (DR), including the role of the cluster (master, replica, or XDCR) and whether DR has started, is running, stopped, or been disabled.

"EXPORT"

Returns statistics on the export streams and targets, including how many records have be written, how many are pending, and the status of the export connection.

"GC"

Returns statistics on Java garbage collection associated with the server process on each host.

"IDLETIME"

Returns statistics on how busy the partitions are. For each execution site, the results provide a minimum, maximum, and average amount of time the site waited without any transactions to process, as well as the overall percentage of time the site was waiting (that is, the partition was "idle").

"IMPORT"

Returns statistics on the import streams, including how many import transactions have succeeded, failed, and been retried and how many rows have been read but not applied yet.

"INDEX"

Returns information about the indexes in the database, including the number of keys for each index and the estimated amount of memory used to store those keys. Separate information is returned for each partition in the database.

"INITIATOR"

Returns information on the number of procedure invocations for each stored procedure (including system and import procedures). The count of invocations is reported for each connection to the database.

"IOSTATS"

Returns information on the number of messages and amount of data (in bytes) sent to and from each connection to the database.

"LATENCY"

Returns statistics on the latency of transactions. The information reports on median, percentage (99% through 99.999%), and maximum latency over the most recent five second sampling period.

"LIMITS"

Returns information about limits on the number file descriptors and, as a consequence, the number of client connections on the servers.

"LIVECLIENTS"

Returns information about the number of outstanding requests per client. You can use this information to determine how much work is waiting in the execution queues.

"MANAGEMENT"

Returns the same information as MEMORY, INITIATOR, PROCEDURE, IOSTATS, TABLE, INDEX, IDLETIME, QUEUE, and CPU, except all in a single procedure call.

"MEMORY"

Returns statistics on the use of memory for each node in the cluster. MEMORY statistics include the current resident set size (RSS) of the VoltDB server process; the amount of memory used for Java temporary storage, database tables, indexes, and string (including varbinary) storage; as well as other information.

"PARTITIONCOUNT"

Returns information on the number of unique partitions in the cluster. The VoltDB cluster creates multiple partitions based on the number of servers and the number of sites per host requested. So, for example, a 2 node cluster with 4 sites per host will have 8 partitions. However, when you define a cluster with K-safety, there are duplicate partitions. PARTITIONCOUNT only reports the number of unique partitions available in the cluster.

"PLANNER"

Returns information on the use of cached plans within each partition. Queries in stored procedures are planned when the procedure is declared in the schema. However, ad hoc queries must be planned at runtime. To improve performance, VoltDB caches plans for ad hoc queries so they can be reused when a similar query is encountered later. There are two caches: the level 1 cache performs exact matches on queries and the level 2 cache parameterizes constants so it can match queries with the same plan but different input. The planner statistics provide information about the size of each cache, how frequently it is used, and the minimum, maximum, and average execution time of ad hoc queries as a result.

"PROCEDURE"

Returns information on the usage of stored procedures for each site within the database cluster sorted by partition. The information includes the name of the procedure, the number of invocations (for each site), and selected performance information on minimum, maximum, and average execution time.

"PROCEDUREDETAIL"

Returns detailed performance information about the individual statements within each stored procedure. PROCEDUREDETAIL returns information for each statement in each procedure, grouped by site and partition within the database cluster. The information includes the name of the procedure, the name of the statement, the number of invocations (for each site), and selected performance information on minimum, maximum, and average execution time.

"PROCEDUREINPUT"

Returns summary information on the size of the input data submitted with stored procedure invocations. PROCEDUREINPUT uses information from PROCEDURE, except it focuses on the input parameters and aggregates data for the entire cluster.

"PROCEDUREOUTPUT"

Returns summary information on the size of the result sets returned by stored procedure invocations. PROCEDUREOUTPUT uses information from PROCEDURE, except it focuses on the result sets and aggregates data for the entire cluster.

"PROCEDUREPROFILE"

Returns summary information on the usage of stored procedures averaged across all partitions in the cluster. The information from PROCEDUREPROFILE is similar to the information from PROCEDURE, except it focuses on the performance of the individual procedures rather than on procedures by partition. The weighted average across partitions is helpful for determining which stored procedures the application is spending most of its time in.

"QUEUE"

Returns statistics on the number of tasks in each partition's process queue and the average and maximum time tasks were waiting in the queue.

"QUEUEPRIORITY"

Returns statistics on the number of tasks in each priority queue for each partition and the average and maximum time tasks were waiting in the queue.

"REBALANCE"

Returns information on the current progress of rebalancing on the cluster. Rebalancing occurs when one or more nodes are added "on the fly" to an elastic cluster. If no rebalancing is occurring, no data is returned. During a rebalance, this selector returns information about the speed of migration of the data, the latency of rebalance tasks, and the estimated time until completion. All rebalance statistics are cumulative for the current rebalance activity.

"SNAPSHOTSTATUS"

Returns information about the individual files of up to ten recent snapshots performed by the database. The results include the directory path and prefix for the snapshot, when it occurred, how long it took, and whether the snapshot was completed successfully or not. The results report on both native and CSV snapshots, as well as manual, automated, and command log snapshots. Note that this selector does not tell you whether the snapshot files still exist, only that the snapshot was performed. Use the @SnapshotScan procedure to determine what snapshots are available.

"SNAPSHOTSUMMARY"

Returns information about up to ten recent snapshots performed by the database. Unlike SNAPSHOTSTATUS, which reports on individual files, SNAPSHOTSUMMARY provides a one row summary for each snapshot. The results include the directory path and prefix, when the snapshot started, how long it took, and whether the snapshot was completed successfully or not. If the snapshot is still in progress, the results include the percentage complete. Note that this selector does not tell you whether the snapshot files still exist, only that the snapshot was started. Use the @SnapshotScan procedure to determine what snapshot files are available.

"TABLE"

Returns information about the database tables, including the number of rows per site for each table. This information can be useful for seeing how well the rows are distributed across the cluster for partitioned tables.

"TASK"

Returns information about scheduled tasks and their current status. There are separate queues for the task schedulers and the task procedures, which run on the standard transactional partition queues. The TASK selector reports on both. Separate selectors for TASK_SCHEDULER and TASK_PROCEDURE report on a corresponding subset of the columns.

"TLS"

Returns statistics about the time it takes to encrypt and decrypt messages for TLS/SSL transmission.

"TOPIC"

Returns statistics about the queues for outbound topics (that is, data fetched by consumers) including throughput, offsets, and retention policy, as well as how much data is currently stored on disk.

"TTL"

Returns information about the processing of expired data in "time to live" (TTL) tables, including how recently and how many records have been deleted. (

Note that INITIATOR and PROCEDURE report information on both user-declared stored procedures and system procedures. These include certain system procedures that are used internally by VoltDB and are not intended to be called by client applications. Only the system procedures documented in this appendix are intended for client invocation.

Return Values

Returns different VoltTables depending on which component is requested. The following tables identify the structure of the return values for each component. (Note that the MANAGEMENT component returns seven VoltTables.)

CLOCKSKEW — Returns rows for every server in the cluster showing clock skew between it and every other server in the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was reported (in milliseconds). Note that the clock skew is calculated and cached periodically (once an hour, by default). It is not evaluated when the procedure is called.
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SKEW_TIMEINTEGERThe number of milliseconds difference between the system clock time of the current host and the remote host.
REMOTE_HOST_IDINTEGERNumeric ID for the remote host node.
REMOTE_HOSTNAMESTRINGServer name of the remote host node.

COMMANDLOG — Returns a row for every server in the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
OUTSTANDING_BYTESBIGINTThe size, in bytes, of pending command log data. That is, data for transactions that have been initiated but the log has yet to be written to disk. For synchronous logging, this value is always zero.
OUTSTANDING_TXNSBIGINTThe size, in number of transactions, of pending command log data. That is, the number of transactions that have been initiated for which the log has yet to be written to disk. For synchronous logging, this value is always zero.
IN_USE_SEGMENT​_COUNTINTEGERThe total number of segment files currently in use for command logging.
SEGMENT_COUNTINTEGERThe number of segment files allocated, including currently unused segments.
FSYNC_INTERVALINTEGERThe average interval, in milliseconds, between the last 10 fsync system calls.

COMPOUNDPROC — Returns rows for every compound procedure that has been executed on the cluster, per procedure per host.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
PROCEDURESTRINGThe name of the compound procedure.
INVOCATIONSBIGINTThe total number of invocations of this procedure on this host.
MIN_ELAPSED_TIMEBIGINTThe minimum elapsed length of time (in nanoseconds) to run the compound procedure.
MAX_ELAPSED_TIMEBIGINTThe maximum elapsed length of time (in nanoseconds) to run the compound procedure.
AVG_ELAPSED_TIMEBIGINTThe average elapsed length of time (in nanoseconds) to run the compound procedure.
ABORTSBIGINTThe number of times the procedure was aborted.
FAILURESBIGINTThe number of times the procedure failed unexpectedly (as opposed to user aborts).

COMPACTION — Returns rows for every table in every partition, per host.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDBIGINTNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDBIGINTNumeric ID of the execution site on the host node.
PARTITION_IDINTEGERThe numeric ID for the logical partition that this site represents. When using a K value greater than zero, there are multiple copies of each logical partition.
TABLE_NAMESTRINGThe name of the database table.
INVOCATIONSBIGINTThe total number of invocations of the compaction procedure for this table and partition
MIN_EXECUTION_TIMEBIGINTThe minimum length of time (in milliseconds) it took to compact the table data for this partition.
MAX_EXECUTION_TIMEBIGINTThe maximum length of time (in milliseconds) it took to compact the table data for this partition.
AVG_EXECUTION_TIMEBIGINTThe average length of time (in milliseconds) it took to compact the table data for this partition.
MIN_RELOCATED_COUNTBIGINTThe minimum number of tuples moved during a compaction event.
MAX_RELOCATED_COUNTBIGINTThe maximum number of tuples moved during a compaction event.
AVG_RELOCATED_COUNTBIGINTThe average number of tuples moved during a compaction event.
MIN_FRAGMENTED_PERCENTFLOATThe minimum percentage of fragmentation found during compaction.
MAX_FRAGMENTED_PERCENTFLOATThe maximum percentage of fragmentation found during compaction.
FRAGMENTED_PERCENTFLOATThe current percentage of fragmentation in the table data for this partition.

COMPOUNDPROCCALLS — Returns a row for every compound procedure and each stored procedure it has invoked, separated by host server.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
PROCEDURESTRINGThe name of the compound procedure.
CALLED _PROCEDURESTRINGThe name of the stored procedure invoked by the compound procedure.
INVOCATIONSBIGINTThe total number of invocations of the stored procedure by the compound procedure on this host.

COMPOUNDPROCSUMMARY — Returns a row for every compound procedure that has been executed on the cluster, aggregated across all nodes of the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
PROCEDURESTRINGThe name of the compound procedure.
INVOCATIONSBIGINTThe total number of invocations of this procedure.
MIN_ELAPSED_TIMEBIGINTThe minimum elapsed length of time (in nanoseconds) to run the compound procedure.
MAX_ELAPSED_TIMEBIGINTThe maximum elapsed length of time (in nanoseconds) to run the compound procedure.
AVG_ELAPSED_TIMEBIGINTThe average elapsed length of time (in nanoseconds) to run the compound procedure.
ABORTSBIGINTThe number of times the procedure was aborted.
FAILURESBIGINTThe number of times the procedure failed unexpectedly (as opposed to user aborts).

CPU — Returns a row for every server in the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
PERCENT_USEDBIGINTThe percentage of total CPU available used by the database server process.

DRCONFLICTS — Returns a row per table per partition per server.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
CLUSTER_IDINTEGERThe numeric ID of the current cluster.
REMOTE_CLUSTER_IDINTEGERThe numeric ID of the remote cluster.
PARTITION_IDINTEGERThe numeric ID for the logical partition.
TABLE_NAMESTRINGThe name of the database table where the conflicts are occurring.
LAST_CONFLICT_TIMESTAMPTIMESTAMPThe timestamp of the last conflict.
TOTAL_CONFLICT_COUNTBIGINTThe total number of conflicts that have been recorded for this table in this partition. This is the sum of the missing row, timestamp mismatch, and constraint violation counts.
DIVERGENCE_COUNTBIGINTThe number of conflicts that may have resulted in divergence between the clusters, which is a subset of the total conflicts.
MISSING_ROW_COUNTBIGINTThe number of missing row conflicts that occurred.
TIMESTAMP_MISMATCH_COUNTBIGINTThe number of timestamp mismatch conflicts that occurred.
CONSTRAINT_VIOLATION_COUNTBIGINTThe number of constraint violation conflicts that occurred.

DRCONSUMER — Returns three VoltTables. The first table returns a row for every host in the cluster, showing whether a replication snapshot is in progress and if it is, the status of transmission to the consumer.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
CLUSTER_IDINTEGERThe numeric ID of the current cluster.
REMOTE_CLUSTER_IDINTEGERThe numeric ID of the producer cluster.
STATESTRING

A text string indicating the current state of replication. Possible values are:

  • UNINITIALIZED — DR has not begun yet or has stopped

  • INITIALIZE — DR is enabled and the consumer is attempting to contact the producer

  • SYNC — DR has started and the consumer is synchronizing by receiving snapshots of existing data from the master

  • RECEIVE — DR is underway and the consumer is receiving binary logs from the master

  • DISABLE — DR has been canceled for some reason and the consumer is stopping DR

REPLICATION_RATE_1MBIGINTThe average rate of replication over the past minute. The data rate is measured in bytes per second.
REPLICATION_RATE_5MBIGINTThe average rate of replication over the past five minutes. The data rate is measured in bytes per second.

The second table contains information about the replication streams, which consist of a row per partition for each server. The data shows the current state of replication and how much data has been received by the consumer from each producer.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
CLUSTER_IDINTEGERThe numeric ID of the current cluster.
REMOTE_CLUSTER_IDINTEGERThe numeric ID of the producer cluster.
PARTITION_IDINTEGERThe numeric ID for the logical partition.
IS_COVEREDSTRINGA text string of "true" or "false" indicating whether this partition is currently connected to and receiving data from a matching partition on the producer cluster.
COVERING_HOSTSTRINGThe host name of the server in the producer cluster that is providing DR data to this partition. If IS_COVERED is "false", this field is empty.
LAST_RECEIVED​_TIMESTAMPTIMESTAMPThe timestamp of the last transaction received from the producer.
LAST_APPLIED​_TIMESTAMPTIMESTAMPThe timestamp of the last transaction successfully applied to this partition on the consumer.
IS_PAUSEDSTRINGA text string of "true" or "false" indicating whether this partition is paused. A partition "pauses" when the schema of the DR tables on the producer change to no longer match the consumer and all binary logs prior to the change have been processed.
DUPLICATE_BUFFERSBIGINTThe number of repeated buffers received after the initial packets were dropped because the queue was full.
IGNORED_BUFFERSBIGINTThe number of buffers received but dropped because the queue was full.
AVAILABLE_BYTESINTEGERThe number of free bytes left in the DR queue.
AVAILABLE_BUFFERSINTEGERThe number of free buffers left in the DR queue.
CONSUMER_LIMIT_TYPESTRINGThe type of limit on the DR queue. The response is either BYTES or BUFFERS.

The third table is primarily for use by support. It returns a row for every host in the cluster with information for use in debugging XDCR issues.

NameDatatypeDescription
CLUSTER_IDINTEGERThe numeric ID of the current cluster.
REMOTE_CLUSTER_IDINTEGERThe numeric ID of the consumer cluster.
STATESTRINGA text string indicating the current state of replication. Possible values are UNINITIALIZED, INITIALIZE, SYNC, RECEIVE, and DISABLE.
LAST_FAILURE_CODEINTEGERA numeric code reserved for use by Volt Active Data support.

DRPRODUCER — Returns two VoltTables. The first table contains information about the replication streams, which consist of a row per partition for each server. The data shows the current state of replication and how much data is currently queued for each consumer.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
CLUSTER_IDINTEGERThe numeric ID of the current cluster.
REMOTE_CLUSTER_IDINTEGERThe numeric ID of the consumer cluster.
PARTITION_IDINTEGERThe numeric ID for the logical partition.
STREAMTYPESTRINGThe type of stream, which can either be "TRANSACTIONS" or "SNAPSHOT".
TOTALBYTESBIGINTThe total number of bytes currently queued for transmission to the consumer.
TOTALBYTES​IN​MEMORYBIGINTThe total number of bytes of queued data currently held in memory. If the amount of total bytes is larger than the amount in memory, the remainder is kept in overflow storage on disk.
TOTALBUFFERSBIGINTThe total number of buffers in this partition currently waiting for acknowledgement from the consumer. The partitions buffer the binary logs to reduce overhead and optimize network transfers.
LASTQUEUEDDRIDBIGINTThe ID of the last transaction queued for transmission to the consumer.
LASTACK​DRIDBIGINTThe ID of the last transaction acknowledged by the consumer.
LASTQUEUEDTIMESTAMPTIMESTAMPThe timestamp of the last transaction queued for transmission to the consumer.
LASTACK​TIMESTAMPTIMESTAMPThe timestamp of the last transaction acknowledged by the consumer.
ISSYNCEDSTRINGA text string indicating whether the database is currently being replicated. If replication has not started, or the overflow capacity has been exceeded (that is, replication has failed), the value of ISSYNCED is "false". If replication is currently in progress, the value is "true".
MODESTRINGA text string indicating whether this particular partition is replicating data to the consumer ("NORMAL") or not ("PAUSED"). Only one copy of each logical partition actually sends data during replication. So for clusters with a K-safety value greater than zero, not all physical partitions will report "NORMAL" even when replication is in progress.
QUEUE_GAPBIGINTThe number of missing transactions between those already acknowledged by the consumer and the next available for transmission. Under normal operating conditions, this value is zero.
CONNECTION​_STATUSSTRINGA text string indicating whether the connection to the consumer is operational ("UP") or not ("DOWN"). If the connection between the producer and consumer is broken or if the producer does not hear from the consumer for more than 30 seconds, the connection is marked as "DOWN".
AVAILABLE_BYTESINTEGERThe number of bytes waiting to be sent to the consumer
AVAILABLE_BUFFERSINTEGERThe number of buffers waiting to be sent to the consumer.
CONSUMER_LIMIT_TYPESTRINGThe type of limit on the DR queue. The response is either BYTES or BUFFERS.
DR_ROUNDTRIPTIME​_1MINUTE_MAXBIGINTThe maximum time it took to receive acknowledgement from the consumer, over the past minute.
DR_ROUNDTRIPTIME​_1MINUTE_AVGBIGINTThe average time it took to receive acknowledgement from the consumer, over the past minute.
DR_ROUNDTRIPTIME​_51MINUTE_MAXBIGINTThe maximum time it took to receive acknowledgement from the consumer, over the past five minutes.
DR_ROUNDTRIPTIME​_5MINUTE_AVGBIGINTThe average time it took to receive acknowledgement from the consumer, over the past five minutes.

The second table returns a row for every host in the cluster, showing whether a replication snapshot is in progress and if it is, the status of transmission to the consumer.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
CLUSTER_IDINTEGERThe numeric ID of the current cluster.
REMOTE_CLUSTER_IDINTEGERThe numeric ID of the consumer cluster.
STATESTRINGA text string indicating the current state of replication. Possible values are "OFF" (replication is not enabled), "PENDING" (replication is enabled but not occurring), and "ACTIVE" (replication is enabled and a replica database has initiated DR).
SYNC​SNAPSHOT​STATESTRINGA text string indicating the current state of the synchronization snapshot that begins replication. During normal operation, this value is "NONE" indicating either that replication is not active or that transactions are actively being replicated. If a synchronization snapshot is in progress, this value provides additional information about the specific activity underway.
ROWSIN​SYNC​SNAPSHOTBIGINTReserved for future use.
ROWSACKED​FORSYNC​SNAPSHOTBIGINTReserved for future use.

DRROLE — Returns one row per connection showing the current status of DR for that cluster.

NameDatatypeDescription
ROLESTRINGThe role of the current cluster in a DR relationship. Possible values are NONE, MASTER, REPLICA, and XDCR. (None indicates that no DR ID is defined and the cluster cannot participate in DR.)
STATESTRING

The current state of the DR relationship. Possible values are the following:

  • DISABLED — DR is not enabled for the cluster

  • PENDING — DR is enabled but communication with the other cluster has not begun

  • ACTIVE — Communication with the other cluster has begun

  • STOPPED — Communication with the other cluster has stopped due to a failure of some kind

Note that if DR stops, issuing the voltadmin dr reset command will return the cluster to the PENDING state.

REMOTE_CLUSTER_IDINTEGERThe DR ID of the other DR cluster, or -1 if not available (for example, when DR is disabled or communication has not begun).

EXPORT — Returns a separate row for each export stream per partition.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDINTEGERNumeric ID of the execution site on the host node.
PARTITION_IDINTEGERThe numeric ID for the logical partition.
SOURCESTRINGThe name of the export stream.
TARGETSTRINGThe name of the export target.
ACTIVESTRING

Whether this site is currently actively exporting data. For normal export in a K-safe cluster, only one copy of each partition actively exports data at any given time. Possible values for user export are "TRUE" and "FALSE".

Note that cross datacenter replication (XDCR) uses the export infrastructure to write the DR conflict logs. In this case, all copies of the partition write the logs and the ACTIVE column is marked as "XDCR" to distinguish it from user-defined export streams.

TUPLE_COUNTBIGINTThe total number of records queued to the export target since the queue was created. (Not affected by the delta flag.)
TUPLE_PENDINGBIGINTThe number of records out of TUPLE_COUNT still waiting to be written to or acknowledged by the target.
LAST_QUEUED_TIMESTAMPTIMESTAMPThe timestamp when the most recent tuple was added to the export queue for this partition (in milliseconds).
LAST_ACKED_TIMESTAMPTIMESTAMPThe timestamp when the last tuple was acknowledged as received by the target (in milliseconds).
AVERAGE_LATENCYBIGINTThe average time between when records are inserted and they are acknowledged by the target.
MAXIMUM_LATENCYBIGINTThe maximum time between when a record was inserted and it was acknowledged by the target.
QUEUE_GAPBIGINTThe number of records missing from the queue for the current stream and partition.
STATUSSTRING

The current status of the export connection. Possible values are the following:

  • ACTIVE — Queue is currently exporting to the target

  • BLOCKED — There is a gap in the queue and export is waiting to see if the missing records become available when a missing node rejoins

  • DROPPED — either the source stream has been dropped from the schema or the export configuration has been removed from the configuration and queue is draining any remaining records

Note that if the queue is blocked, the voltadmin export release command returns the queue to the ACTIVE state.

GC — Returns a separate row for each host.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
NEWGEN_GC_COUNTINTEGERThe number of times "young generation" garbage collection was performed.
NEWGEN_AVG_GC_TIMEBIGINTThe average time (in milliseconds) taken by young generation collections.
OLDGEN_GC_COUNTINTEGERThe number of times "old generation" garbage collection was performed.
OLDGEN_AVG_GC_TIMEBIGINTThe average time (in milliseconds) taken by old generation collections.

IDLETIME — Returns a separate row for each execution site and host.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDINTEGERNumeric ID of the execution site on the host node.
COUNTBIGINTThe number of times the execution site had to wait for a new task (that is, the queue was empty).
PERCENTFLOATThe percentage of time the execution site was waiting for a new task (that is, the site was "idle").
AVGBIGINTThe average amount of time the execution site had to wait for a new task (in microseconds).
MINBIGINTThe minimum amount of time the execution site had to wait for a new task (in nanoseconds).
MAXBIGINTThe maximum amount of time the execution site had to wait for a new task (in nanoseconds).
STDDEVBIGINTThe standard deviation of the waiting time (in microseconds).

IMPORT — Returns a separate row for each import stream and each server.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDINTEGERNumeric ID of the execution site on the host node.
IMPORTER_NAMESTRINGThe name of the import stream.
PROCEDURE_NAMESTRINGThe name of the stored procedure invoked by the import stream to insert the incoming data.
SUCCESSESBIGINTThe number of import transactions that succeeded.
FAILURESBIGINTThe number of import transactions that failed.
OUTSTANDING​_REQUESTSBIGINTThe number of records read from the import stream and waiting to be inserted into the database.
RETRIESBIGINTThe number of attempts to replay failed transactions.

INDEX — Returns a row for every index in every execution site.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDINTEGERNumeric ID of the execution site on the host node.
PARTITION_IDBIGINTThe numeric ID for the logical partition that this site represents. When using a K value greater than zero, there are multiple copies of each logical partition.
INDEX_NAMESTRINGThe name of the index.
TABLE_NAMESTRINGThe name of the database table to which the index applies.
INDEX_TYPESTRING

A text string identifying whether the index is unique or not. Possible values include the following:

CompactingTreeMultiMapIndex
CompactingTreeUniqueIndex
IS_UNIQUETINYINTA byte value specifying whether the index is unique (1) or not (0).
IS_COUNTABLETINYINTA byte value specifying whether the index maintains a counter to optimize COUNT(*) queries.
ENTRY_COUNTBIGINTThe number of index entries currently in the partition.
MEMORY_ESTIMATEBIGINTThe estimated amount of memory (in kilobytes) consumed by the current index entries.

INITIATOR — Returns a separate row for each connection and the stored procedures initiated by that connection.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDINTEGERNumeric ID of the execution site on the host node.
CONNECTION_IDBIGINTNumeric ID of the client connection invoking the procedure.
CONNECTION_HOST​NAMESTRINGThe server name of the node from which the client connection originates. In the case of import procedures, the name of the importer is reported here.
PROCEDURE_NAMESTRINGThe name of the stored procedure. If import is enabled, import procedures are included as well.
INVOCATIONSBIGINTThe number of times the stored procedure has been invoked by this connection on this host node.
AVG_EXECUTION_TIMEINTEGERThe average length of time (in milliseconds) it took to execute the stored procedure.
MIN_EXECUTION_TIMEINTEGERThe minimum length of time (in milliseconds) it took to execute the stored procedure.
MAX_EXECUTION_TIMEINTEGERThe maximum length of time (in milliseconds) it took to execute the stored procedure.
ABORTSBIGINTThe number of times the procedure was aborted.
FAILURESBIGINTThe number of times the procedure failed unexpectedly. (As opposed to user aborts or expected errors, such as constraint violations.)

IOSTATS — Returns one row for every client connection on the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
CONNECTION_IDBIGINTNumeric ID of the client connection invoking the procedure.
CONNECTION_HOST​NAMESTRINGThe server name of the node from which the client connection originates.
BYTES_READBIGINTThe number of bytes of data sent from the client to the host.
MESSAGES_READBIGINTThe number of individual messages sent from the client to the host.
BYTES_WRITTENBIGINTThe number of bytes of data sent from the host to the client.
MESSAGES_WRITTENBIGINTThe number of individual messages sent from the host to the client.

LATENCY — Returns a row for every server in the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp, in milliseconds, when the data was collected (not when the call was processed). If two calls to this selector return the same timestamp, the data being returned is identical.
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
INTERVALINTEGERThe length of the measurement interval, in milliseconds. The interval is five seconds (5000).
COUNTINTEGERThe total number of transactions during the interval.
TPSINTEGERThe number of transactions per second during the interval.
P50BIGINTThe 50th percentile latency, in microseconds. This value measures the median latency.
P95BIGINTThe 95th percentile latency, in microseconds.
P99BIGINTThe 99th percentile latency, in microseconds.
P99.9BIGINTThe 99.9th percentile latency, in microseconds.
P99.99BIGINTThe 99.99th percentile latency, in microseconds.
P99.999BIGINTThe 99.999th percentile latency, in microseconds.
MAXBIGINTThe maximum latency during the interval, in microseconds.

LIMITS — Returns a row for every server in the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was reported (in milliseconds). Note that the number of file descriptors (maximum and currently open) is calculated periodically and cached rather than at the time of each call.
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
FILE_DESCRIPTORS_LIMITINTEGERThe maximum number of file descriptors allowed for the process running the server.
FILE_DESCRIPTORS_OPENINTEGERThe number of file descriptors currently open in the process.
CLIENT_CONNECTIONS_LIMITINTEGERThe maximum number of client connections allowed for the server.
CLIENT_CONNECTIONS_OPENINTEGERThe number of client connections currently open on the server.
ACCEPTED_CONNECTIONSINTEGERThe total number of client connections opened since the server started, including connections that are now closed.
DROPPED_CONNECTIONSINTEGERThe total number of connections that were rejected because the connection limit had been reached.

LIVECLIENTS — Returns two VoltTables. The first contains one row for every client connection currently active on the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
CONNECTION_IDBIGINTNumeric ID of the client connection invoking the procedure.
CLIENT_HOSTNAMESTRINGThe server name of the node from which the client connection originates.
ADMINTINYINTA byte value specifying whether the connection is to the client port (0) or the admin port (1).
OUTSTANDING_​REQUEST_BYTESBIGINTThe number of bytes of data sent from the client currently pending on the host.
OUTSTANDING_​RESPONSE_MESSAGESBIGINTThe number of messages on the host queue waiting to be retrieved by the client.
OUTSTANDING_​TRANSACTIONSBIGINTThe number of transactions (that is, stored procedures) initiated on behalf of the client that have yet to be completed.

The second VoltTable returns one row for every server in the cluster. Note this second table repeats the information returned by the LIMITS selector.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was reported (in milliseconds). Note that due to the resources needed to determine the number of file descriptors (maximum and currently open), this information is calculated periodically and cached rather than at the time of each call.
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
FILE_DESCRIPTORS_LIMITINTEGERThe maximum number of file descriptors allowed for the process running the server.
FILE_DESCRIPTORS_OPENINTEGERThe number of file descriptors currently open in the process
CLIENT_CONNECTIONS_LIMITINTEGERThe maximum number of client connections allowed for the server.
CLIENT_CONNECTIONS_OPENINTEGERThe number of client connections currently open on the server.
ACCEPTED_CONNECTIONSINTEGERThe total number of client connections opened since the server started, including connections that are now closed.
DROPPED_CONNECTIONSINTEGERThe total number of connections that were rejected because the connection limit had been reached.

MEMORY — Returns a row for every server in the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
RSSINTEGERThe current resident set size. That is, the total amount of memory allocated to the VoltDB processes on the server.
JAVAUSEDINTEGERThe amount of memory (in kilobytes) allocated by Java and currently in use by VoltDB.
JAVAUNUSEDINTEGERThe amount of memory (in kilobytes) allocated by Java but unused. (In other words, free space in the Java heap.)
TUPLEDATABIGINTThe amount of memory (in kilobytes) currently in use for storing database records.
TUPLEALLOCATEDBIGINTThe amount of memory (in kilobytes) allocated for the storage of database records (including free space).
INDEXMEMORYBIGINTThe amount of memory (in kilobytes) currently in use for storing database indexes.
STRINGMEMORYBIGINTThe amount of memory (in kilobytes) currently in use for storing string, binary, and geospatial data that is not stored "in-line" in the database record.
TUPLECOUNTBIGINTThe total number of database records currently in memory.
POOLEDMEMORYBIGINTThe total size of memory (in kilobytes) allocated for tasks other than database records, indexes, and strings. (For example, pooled memory is used for temporary tables while processing stored procedures.)
PHYSICALMEMORYBIGINTThe total size of physical memory (in kilobytes) on the server.
JAVAMAXHEAPINTEGERThe maximum heap size (in kilobytes) of the Java runtime environment.

PARTITIONCOUNT — Returns one row identifying the total number of partitions and the host that provided that information.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
PARTITION_COUNTINTEGERThe number of unique or logical partitions on the cluster. When using a K value greater than zero, there are multiple copies of each logical partition.

PLANNER — Returns a row for every planner cache. That is, one cache per execution site, plus one global cache per server. (The global cache is identified by a site and partition ID of minus one.)

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDINTEGERNumeric ID of the execution site on the host node.
PARTITION_IDINTEGERThe numeric ID for the logical partition that this site represents. When using a K value greater than zero, there are multiple copies of each logical partition.
CACHE1_LEVELINTEGERThe number of query plans in the level 1 cache.
CACHE2_LEVELINTEGERThe number of query plans in the level 2 cache.
CACHE1_HITSBIGINTThe number of queries that matched and reused a plan in the level 1 cache.
CACHE2_HITSBIGINTThe number of queries that matched and reused a plan in the level 2 cache.
CACHE_MISSESBIGINTThe number of queries that had no match in the cache and had to be planned from scratch
PLAN_TIME_MINBIGINTThe minimum length of time (in nanoseconds) it took to complete the planning of ad hoc queries.
PLAN_TIME_MAXBIGINTThe maximum length of time (in nanoseconds) it took to complete the planning of ad hoc queries.
PLAN_TIME_AVGBIGINTThe average length of time (in nanoseconds) it took to complete the planning of ad hoc queries.
FAILURESBIGINTThe number of times planning for an ad hoc query failed.

PROCEDURE — Returns a row for every stored procedure that has been executed on the cluster, grouped by execution site.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDINTEGERNumeric ID of the execution site on the host node.
PARTITION_IDINTEGERThe numeric ID for the logical partition that this site represents. When using a K value greater than zero, there are multiple copies of each logical partition.
PROCEDURESTRINGThe class name of the stored procedure.
INVOCATIONSBIGINTThe total number of invocations of this procedure at this site.
TIMED_INVOCATIONSBIGINTThe number of invocations used to measure the minimum, maximum, and average execution time.
MIN_EXECUTION_TIMEBIGINTThe minimum length of time (in nanoseconds) it took to execute the stored procedure.
MAX_EXECUTION_TIMEBIGINTThe maximum length of time (in nanoseconds) it took to execute the stored procedure.
AVG_EXECUTION_TIMEBIGINTThe average length of time (in nanoseconds) it took to execute the stored procedure.
MIN_RESULT_SIZEINTEGERThe minimum size (in bytes) of the results returned by the procedure.
MAX_RESULT_SIZEINTEGERThe maximum size (in bytes) of the results returned by the procedure.
AVG_RESULT_SIZEINTEGERThe average size (in bytes) of the results returned by the procedure.
MIN_PARAMETER​_SET_SIZEINTEGERThe minimum size (in bytes) of the parameters passed as input to the procedure.
MAX_PARAMETER​_SET_SIZEINTEGERThe maximum size (in bytes) of the parameters passed as input to the procedure.
AVG_PARAMETER​_SET_SIZEINTEGERThe average size (in bytes) of the parameters passed as input to the procedure.
ABORTSBIGINTThe number of times the procedure was aborted.
FAILURESBIGINTThe number of times the procedure failed unexpectedly. (As opposed to user aborts or expected errors, such as constraint violations.)
TRANSACTIONALTINYINT0 or 1. Reserved for future use.

PROCEDUREDETAIL — Returns a row for every statement in every stored procedure that has been executed on the cluster, grouped by execution site.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDINTEGERNumeric ID of the execution site on the host node.
PARTITION_IDINTEGERThe numeric ID for the logical partition that this site represents. When using a K value greater than zero, there are multiple copies of each logical partition.
PROCEDURESTRINGThe class name of the stored procedure.
STATEMENTSTRINGThe name of the statement in the stored procedure. Cumulative statistics for all statements in the procedure are included in a separate row labeled "<ALL>".
INVOCATIONSBIGINTThe total number of invocations of the statement at this site.
TIMED_INVOCATIONSBIGINTThe number of invocations used to measure the minimum, maximum, and average execution time.
MIN_EXECUTION_TIMEBIGINTThe minimum length of time (in nanoseconds) it took to execute the statement.
MAX_EXECUTION_TIMEBIGINTThe maximum length of time (in nanoseconds) it took to execute the statement.
AVG_EXECUTION_TIMEBIGINTThe average length of time (in nanoseconds) it took to execute the statement.
MIN_RESULT_SIZEINTEGERThe minimum size (in bytes) of the results returned by the statement.
MAX_RESULT_SIZEINTEGERThe maximum size (in bytes) of the results returned by the statement.
AVG_RESULT_SIZEINTEGERThe average size (in bytes) of the results returned by the statement.
MIN_PARAMETER​_SET_SIZEINTEGERThe minimum size (in bytes) of the parameters passed as input to the statement.
MAX_PARAMETER​_SET_SIZEINTEGERThe maximum size (in bytes) of the parameters passed as input to the statement.
AVG_PARAMETER​_SET_SIZEINTEGERThe average size (in bytes) of the parameters passed as input to the statement.
ABORTSBIGINTIn the cumulative row for each procedure ("<ALL>"), the number of times the procedure was aborted. For individual statements, this column is set to zero.
FAILURESBIGINTThe number of times the statement failed unexpectedly. (As opposed to user aborts or expected errors, such as constraint violations.)

PROCEDUREINPUT — Returns a row for every stored procedure that has been executed on the cluster, summarized across the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
PROCEDURESTRINGThe class name of the stored procedure.
WEIGHTED_PERCBIGINTA weighted average expressed as a percentage of the parameter set size for invocations of this stored procedure compared to all stored procedure invocations.
INVOCATIONSBIGINTThe total number of invocations of this procedure.
MIN_PARAMETER​_SET_SIZEBIGINTThe minimum parameter set size in bytes.
MAX_PARAMETER​_SET_SIZEBIGINTThe maximum parameter set size in bytes.
AVG_PARAMETER​_SET_SIZEBIGINTThe average parameter set size in bytes.
TOTAL_PARAMETER​_SET_SIZE_MBBIGINTThe total input for all invocations of this stored procedure measured in megabytes.

PROCEDUREOUTPUT — Returns a row for every stored procedure that has been executed on the cluster, summarized across the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
PROCEDURESTRINGThe class name of the stored procedure.
WEIGHTED_PERCBIGINTA weighted average expressed as a percentage of the result set size returned by invocations of this stored procedure compared to all stored procedure invocations.
INVOCATIONSBIGINTThe total number of invocations of this procedure.
MIN_RESULT_SIZEBIGINTThe minimum result set size in bytes.
MAX_RESULT_SIZEBIGINTThe maximum result set size in bytes.
AVG_RESULT_SIZEBIGINTThe average result set size in bytes.
TOTAL_RESULT​_SIZE_MBBIGINTThe total output returned by all invocations of this stored procedure measured in megabytes.

PROCEDUREPROFILE — Returns a row for every stored procedure that has been executed on the cluster, summarized across the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
PROCEDURESTRINGThe class name of the stored procedure.
WEIGHTED_PERCBIGINTA weighted average expressed as a percentage of the execution time for this stored procedure compared to all stored procedure invocations.
INVOCATIONSBIGINTThe total number of invocations of this procedure.
AVGBIGINTThe average length of time (in nanoseconds) it took to execute the stored procedure.
MINBIGINTThe minimum length of time (in nanoseconds) it took to execute the stored procedure.
MAXBIGINTThe maximum length of time (in nanoseconds) it took to execute the stored procedure.
ABORTSBIGINTThe number of times the procedure was aborted.
FAILURESBIGINTThe number of times the procedure failed unexpectedly. (As opposed to user aborts or expected errors, such as constraint violations.)

QUEUE — Returns a separate row for each partition and host listing the current state of the process queue for that execution site.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDINTEGERNumeric ID of the execution site on the host node.
CURRENT_DEPTHINTEGERThe number of tasks currently in the queue.
POLL_COUNTBIGINTThe number of tasks that left the queue (and started executing) in the past five seconds.
AVG_WAITBIGINTThe average length of time (in microseconds) tasks were waiting in the queue in the last five seconds.
MAX_WAITBIGINTThe maximum length of time (in microseconds) tasks were waiting in the queue in the last five seconds.

QUEUEPRIORITY — Returns a separate row for each partition and host listing the current state of the priority queues for that execution site (if prioritization is enabled).

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDINTEGERNumeric ID of the execution site on the host node.
PRIORITYINTEGERThe priority of the tasks in the queue.
CURRENT_DEPTHINTEGERThe number of tasks currently in the queue.
POLL_COUNTBIGINTThe number of tasks that left the queue (and started executing) in the past five seconds.
AVG_WAITBIGINTThe average length of time (in microseconds) tasks were waiting in the queue in the last five seconds.
MAX_WAITBIGINTThe maximum length of time (in microseconds) tasks were waiting in the queue in the last five seconds.

REBALANCE — Returns one row if the cluster is rebalancing. No data is returned if the cluster is not rebalancing.

NameDatatypeDescription
TOTAL_RANGESBIGINTThe total number of partition segments to be migrated.
PERCENTAGE_MOVEDFLOATThe percentage of the total segments that have already been moved.
MOVED_ROWSBIGINTThe number of rows of data that have been moved.
ROWS_PER_SECONDFLOATThe average number of rows moved per second.
ESTIMATED​_REMAININGBIGINTThe estimated time remaining until the rebalance is complete, in milliseconds.
MEGABYTES_PER​_SECONDFLOATThe average volume of data moved per second, measured in megabytes.
CALLS_PER_SECONDFLOATThe average number of rebalance work units, or transactions, executed per second.
CALLS_LATENCYFLOATThe average total time between start and finish of rebalance operations, in milliseconds.
CALLS_TIMEFLOATThe average execution time for rebalance transactions, in milliseconds.
CALLS_TRANSFER_TIMEFLOATThe average time spent transferring data during rebalance transactions, in milliseconds.

SNAPSHOTSTATUS — Returns a row for every snapshot file in the recent snapshots performed on the cluster.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
TABLESTRINGThe name of the database table whose data the file contains.
PATHSTRINGThe directory path where the snapshot file resides.
FILENAMESTRINGThe file name.
NONCESTRINGThe unique identifier for the snapshot.
TXNIDBIGINTThe transaction ID of the snapshot.
START_TIMEBIGINTThe timestamp when the snapshot began (in milliseconds).
END_TIMEBIGINTThe timestamp when the snapshot was completed (in milliseconds).
SIZEBIGINTThe total size, in bytes, of the file.
DURATIONBIGINTThe length of time (in seconds) it took to complete the snapshot.
THROUGHPUTFLOATThe average number of bytes per second written to the file during the snapshot process.
RESULTSTRINGString value indicating whether the writing of the snapshot file was successful ("SUCCESS") or not ("FAILURE").
TYPESTRING

String value indicating how the snapshot was initiated. Possible values are:

  • AUTO — an automated snapshot as defined by the configuration file

  • COMMANDLOG — a command log snapshot

  • MANUAL — a manual snapshot initiated by a user

SNAPSHOTSUMMARY — Returns a row for every snapshot performed by the cluster, including up to ten snapshots

NameDatatypeDescription
NONCESTRINGThe unique identifier for the snapshot.
TXNIDBIGINTThe transaction ID of the snapshot.
TYPESTRING

String value indicating how the snapshot was initiated. Possible values are:

  • AUTO — an automated snapshot as defined by the configuration file

  • COMMANDLOG — a command log snapshot

  • MANUAL — a manual snapshot initiated by a user

PATHSTRINGThe target directory path for the snapshot files.
START_TIMEBIGINTThe timestamp when the snapshot began (in milliseconds).
END_TIMEBIGINTThe timestamp when the snapshot was completed (in milliseconds).
DURATIONBIGINTThe length of time (in seconds) it took to complete the snapshot.
PROGRESS_PCTFLOATFor snapshots currently in progress, the percent complete at the time of the call.
RESULTSTRINGString value indicating whether the writing of the snapshot was successful ("SUCCESS") or not ("FAILURE").

TABLE — Returns a row for every table, per partition. In other words, the number of tables, multiplied by the number of sites per host and the number of hosts.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDBIGINTNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDBIGINTNumeric ID of the execution site on the host node.
PARTITION_IDBIGINTThe numeric ID for the logical partition that this site represents. When using a K value greater than zero, there are multiple copies of each logical partition.
TABLE_NAMESTRINGThe name of the database table.
TABLE_TYPESTRINGThe type of the table. Values returned include "PersistentTable" for normal data tables and views and "StreamedTable" for streams.
TUPLE_COUNTBIGINTThe number of rows currently stored for this table in the current partition. For streams, the cumulative total number of rows inserted into the stream.
TUPLE_ALLOCATED​_MEMORYBIGINTThe total size of memory, in kilobytes, allocated for storing inline data associated with this table in this partition. The allocated memory can exceed the currently used memory (TUPLE_DATA_MEMORY). For streams, this field identifies the amount of memory currently in use to queue export data (both in memory and as export overflow) prior to its being passed to the export target.
TUPLE_DATA_MEMORYBIGINTThe total memory, in kilobytes, used for storing inline data associated with this table in this partition. The total memory used for storing data for this table is the combination of memory used for inline (tuple) and non-inline (string) data.
STRING_DATA​_MEMORYBIGINTThe total memory, in kilobytes, used for storing non-inline variable length data (VARCHAR, VARBINARY, and GEOGRAPHY) associated with this table in this partition. The total memory used for storing data for this table is the combination of memory used for inline (tuple) and non-inline (string) data.
TUPLE_LIMITINTEGERUnused. Returns zero.
PERCENT_FULLINTEGERUnused. Returns zero.
DRSTRINGA text string of "true" or "false" indicating whether the table is a DR table or not.
EXPORTSTRINGIf the table or stream is configured with MIGRATE or EXPORT TO TARGET, the name of the associated export target.

TASK — Returns a row for every task, per logical partition.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDBIGINTNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
PARTITION_IDBIGINTThe numeric ID for the logical partition running the task procedure. Directed procedures run on each logical partition. Multi-partition procedures run on the multi-partition initiator.
TASK_NAMESTRINGThe name of the task.
STATESTRING

The current status of the task. Possible values include:

  • RUNNING — The task is enabled and running normally.

  • DISABLED — The task is disabled and not running.

  • ERROR — The task returned an error and was stopped due to the ON ERROR STOP attribute.

  • PAUSED — The database is paused or is running on a DR replica, so the task is not currently running but will restart when the database resumes or is promoted.

SCOPESTRINGThe execution scope of the task, which matches the RUN ON attribute. Possible values are DATABASE, HOSTS, or PARTITIONS.
SCHEDULER_INVOCATIONSBIGINTThe total number of invocations of the task's schedule. For example, if the task is scheduled for every 5 minutes, after 20 minutes of normal operation you would expect 4 invocations.
SCHEDULER_TOTAL_EXECUTIONBIGINTThe total time, in nanoseconds, consumed by the scheduler for scheduling the task.
SCHEDULER_MIN_EXECUTIONBIGINTThe minimum amount of time, in nanoseconds, taken by the scheduler to schedule an instance of the task.
SCHEDULER_MAX_EXECUTIONBIGINTThe maximum amount of time, in nanoseconds, taken by the scheduler to schedule an instance of the task.
SCHEDULER_AVG_EXECUTIONBIGINTThe average amount of time, in nanoseconds, taken by the scheduler to schedule instances of the task.
SCHEDULER_TOTAL_WAIT_TIMEBIGINTThe total time, in nanoseconds, between the task's scheduled start and when the scheduler was invoked.
SCHEDULER_MIN_WAIT_TIMEBIGINTThe minimum difference, in nanoseconds, between when the task was scheduled to run and when the scheduler was invoked.
SCHEDULER_MAX_WAIT_TIMEBIGINTThe maximum difference, in nanoseconds, between when the task was scheduled to run and when the scheduler was invoked.
SCHEDULER_AVG_WAIT_TIMEBIGINTThe average difference, in nanoseconds, between when the task was scheduled to run and when the scheduler was invoked.
SCHEDULER_STATUSSTRINGFor future use.
PROCEDURE_INVOCATIONSBIGINTThe total number of invocations of the task's procedure.
PROCEDURE_TOTAL_EXECUTIONBIGINTThe total time, in nanoseconds, consumed by the task for all of its invocations.
PROCEDURE_MIN_EXECUTIONBIGINTThe minimum amount of time, in nanoseconds, an instance of the task took to execute.
PROCEDURE_MAX_EXECUTIONBIGINTThe maximum amount of time, in nanoseconds, an instance of the task took to execute.
PROCEDURE_AVG_EXECUTIONBIGINTThe average amount of time, in nanoseconds, instances of the task took to execute.
PROCEDURE_TOTAL_WAIT_TIMEBIGINTThe total time, in nanoseconds, between when the procedure was scheduled to run and when it was invoked.
PROCEDURE_MIN_WAIT_TIMEBIGINTThe minimum difference, in nanoseconds, between when the procedure was scheduled to run and when it was invoked.
PROCEDURE_MAX_WAIT_TIMEBIGINTThe maximum difference, in nanoseconds, between when the procedure was scheduled to run and when it was invoked.
PROCEDURE_AVG_WAIT_TIMEBIGINTThe average difference, in nanoseconds, between when the procedure was scheduled to run and when it was invoked.
PROCEDURE_FAILURESBIGINTThe number of times the procedure generated an error when run.

TLS — Returns a separate row for each topic and partition.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDBIGINTNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
CONNECTION_IDBIGINTNumeric ID of the client connection.
CONNECTION_HOST​NAMESTRINGThe server name of the node from which the client connection originates.
MESSAGES_ENCRYPTEDBIGINTThe total number of messages encrypted for output.
AVERAGE_ENCRYPT_LATENCYBIGINTThe average time, in nanoseconds, to encrypt the messages.
MESSAGES_DECRYPTEDBIGINTThe total number of messages decrypted on input.
AVERAGE_DECRYPT_LATENCYBIGINTThe average time, in nanoseconds, to decrypt the messages.

TOPIC — Returns a separate row for each topic and partition.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
HOST_IDINTEGERNumeric ID for the host node.
HOSTNAMESTRINGServer name of the host node.
SITE_IDINTEGERNumeric ID of the execution site on the host node.
TOPICSTRINGThe name of the topic.
PARTITION_IDINTEGERThe numeric ID for the logical partition.
FIRST_OFFSETBIGINTThe value of the first offset currently available in the topic.
LAST_OFFSETBIGINTThe value of the last offset in the topic.
FIRST_OFFSET_TIMESTAMPTIMESTAMPThe timestamp when the first offset was inserted into the queue.
LAST_OFFSET_TIMESTAMPTIMESTAMPThe timestamp when the most recent message (the last offset) was inserted into the queue.
BYTES_ON_DISKBIGINTThe size, in bytes, of data stored on disk for this partition and topic.
BYTES_FETCHEDBIGINTThe size, in bytes, of data sent to consumers for this partition and topic.
STATESTRING

The current level of completeness for this topic in this partition. If the server was down at any point, it may be missing records that were queued while the partition was offline. Possible values are:

  • STABLE — the queue is complete.

  • BACKFILLING — records are missing but are being retrieved from other servers.

  • BLOCKED — records are missing from all copies of the partition.

  • ORPHANED — the queue is no longer being served by this partition, but is saved in case other copies of the queue are blocked or backfilling and need the data. This is a transitional state and the queue is deleted as soon as no other copies need its records.

If a topic becomes blocked and the cluster is complete (has no missing nodes), you can use the voltadmin topic release command to "jump" past the missing offsets.

MASTERSTRINGA text string of "true" or "false" indicating whether the current site is the master for the logical partition.
RETENTION_POLICYSTRINGThe retention policy for this topic.
ROWS_SKIPPEDBIGINTReserved for future use.
ERROR_OFFSETBIGINTIf an error occurs while encoding a message for consumers, an error is returned to the consumer, the offset of the message is recoded here, and a description of the error stored in the next column.
ERROR_MESSAGEBIGINTA description of the last error that occurred while encoding messages for consumers.

TTL — Returns a separate row for each table in the database where TTL processing is currently active. It does not list tables that do not have TTL defined or where TTL processing has been cancelled due to an error or lack of a suitable index.

NameDatatypeDescription
TIMESTAMPBIGINTThe timestamp when the information was collected (in milliseconds).
TABLE_NAMESTRINGThe name of the table.
ROWS_DELETEDBIGINTThe total number of rows expired and deleted by the TTL attribute.
ROWS_DELETED​_LAST​_ROUNDBIGINTThe number of rows expired and deleted during the last TTL processing.
ROWS_REMAININGBIGINTThe number of expired rows not deleted during the last TTL processing due to batch size limits. If TTL processing is keeping up with the throughput, this value should tend towards zero.
LAST_DELETE​_TIMESTAMPBIGINTThe timestamp when the last round of TTL processing occurred (in milliseconds).

Examples

The following example uses @Statistics to gather information about the distribution of table rows within the cluster:

$ sqlcmd
1> exec @Statistics TABLE, 0;

The next program example shows a procedure that collects and displays the number of transactions (i.e. stored procedures) during a given interval, by setting the delta flag to a non-zero value. By calling this procedure iteratively (for example, every five minutes), it is possible to identify fluctuations in the database workload over time (as measured by the number of transactions processed).

void measureWorkload() {
  VoltTable[] results = null;
  String procName;
  int procCount = 0;
  int sysprocCount = 0;

  try { results = client.callProcedure("@Statistics",
                  "INITIATOR",1).getResults(); }
  catch (Exception e) { e.printStackTrace(); }

  for (VoltTable t: results) { 
     for (int r=0;r<t.getRowCount();r++) {
         VoltTableRow row = t.fetchRow(r);
         procName = row.getString("PROCEDURE_NAME");
                /* Count system procedures separately */
         if (procName.substring(0,1).compareTo("@") == 0)
           { sysprocCount += row.getLong("INVOCATIONS"); }
         else 
           { procCount += row.getLong("INVOCATIONS"); }
     }
  }
  System.out.printf("System procedures: %d\n" +
                    "User-defined procedures: %d\n",+
                    sysprocCount,procCount);
}