Throughput and latency

Monitor query processing and database IOPS

YugabyteDB supports additional attributes for latency metrics, which enable you to calculate throughput.

These attributes include the following:

Attribute Description
total_count/count The number of times the value of a metric has been measured.
min The minimum value of a metric across all measurements.
mean The average value of the metric across all measurements.
Percentile_75 The 75th percentile value of the metric across all measurements.
Percentile_95 The 95th percentile value of the metric across all measurements.
Percentile_99 The 99th percentile of the metric across all metrics measurements.
Percentile_99_9 The 99.9th percentile of the metric across all metrics measurements.
Percentile_99_99 The 99.99th percentile of the metric across all metrics measurements.
max The maximum value of the metric across all measurements.
total_sum/sum The aggregate of all the metric values across the measurements reflected in total_count/count.

For example, if SELECT * FROM table is executed once and returns 8 rows in 10 microseconds, the handler_latency_yb_ysqlserver_SQLProcessor_SelectStmt metric would have the following attribute values: total_count=1, total_sum=10, min=10, max=10, and mean=10. If the same query is run again and returns in 6 microseconds, then the attributes would be as follows: total_count=2, total_sum=16, min=6, max=10, and mean=8.

Although these attributes are present in all handler_latency metrics, they may not be calculated for all the metrics.

YSQL query processing

YSQL query processing metrics represent the total inclusive time it takes YugabyteDB to process a YSQL statement after the query processing layer begins execution. These metrics include the time taken to parse and execute the SQL statement, replicate over the network, the time spent in the storage layer, and so on. The preceding metrics do not capture the time to deserialize the network bytes and parse the query.

The following are key metrics for evaluating YSQL query processing.

Metric Unit Type Description
handler_latency_yb_ysqlserver_SQLProcessor_InsertStmt microseconds counter Time to parse and execute INSERT statement.
handler_latency_yb_ysqlserver_SQLProcessor_SelectStmt microseconds counter Time to parse and execute SELECT statement.
handler_latency_yb_ysqlserver_SQLProcessor_UpdateStmt microseconds counter Time to parse and execute UPDATE statement.
handler_latency_yb_ysqlserver_SQLProcessor_BeginStmt microseconds counter Time to parse and execute transaction BEGIN statement.
handler_latency_yb_ysqlserver_SQLProcessor_CommitStmt microseconds counter Time to parse and execute transaction COMMIT statement.
handler_latency_yb_ysqlserver_SQLProcessor_RollbackStmt microseconds counter Time to parse and execute transaction ROLLBACK statement.
handler_latency_yb_ysqlserver_SQLProcessor_OtherStmts microseconds counter Time to parse and execute all other statements apart from the preceding ones listed in this table. Includes statements like PREPARE, RELEASE SAVEPOINT, and so on.
handler_latency_yb_ysqlserver_SQLProcessor_Transactions microseconds counter Time to execute any of the statements in this table.

The YSQL throughput can be viewed as an aggregate across the whole cluster, per table, and per node by applying the appropriate aggregations.

Database IOPS (reads and writes)

The YB-TServer is responsible for the actual I/O of client requests in a YugabyteDB cluster. Each node in the cluster has a YB-TServer, and each hosts one or more tablet peers.

The following are key metrics for evaluating database IOPS.

Metric Unit Type Description
handler_latency_yb_tserver_TabletServerService_Read microseconds counter Time to perform WRITE operations at a tablet level.
handler_latency_yb_tserver_TabletServerService_Write microseconds counter Time to perform READ operations at a tablet level.

These metrics can be viewed as an aggregate across the whole cluster, per table, and per node by applying the appropriate aggregations.