This topic describes monitoring metrics related to the Request waiting queue within an OceanBase Database tenant. These metrics are enqueue_count and dequeue_count. You can specify a statistical period to query statistics about the Request waiting queue in a single zone or on a single OBServer of an OceanBase Database tenant.
enqueue_count
Definition
The average number of SQL statements that are added to the queue per second in the specified statistical period.
Description
| Metric | Metric field name | Unit |
|---|---|---|
| enqueue_count | request_enqueue_count | times/s |
Calculation expression
sum(rate(ob_sysstat{stat_id="20000",@LABELS}[@INTERVAL])) by (@GBLABELS)
SQL statements for metric collection
If you use OceanBase Database of a version earlier than V4.0, execute the following statement:
select /*+ MONITOR_AGENT READ_CONSISTENCY(WEAK) */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (20000) and (con_id > 1000 or con_id = 1) and class < 1000If you use OceanBase Database V4.0 or later, execute the following statement:
select /* MONITOR_AGENT */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (20000) and (con_id > 1000 or con_id = 1) and class < 1000
dequeue_count
Definition
The average number of SQL statements that are removed from the queue per second in the specified statistical period.
Description
| Metric | Metric field name | Unit |
|---|---|---|
| dequeue_count | request_queue_count | times/s |
Calculation expression
sum(rate(ob_sysstat{stat_id="20001",@LABELS}[@INTERVAL])) by (@GBLABELS)
SQL statements for metric collection
If you use OceanBase Database of a version earlier than V4.0, execute the following statement:
select /*+ MONITOR_AGENT READ_CONSISTENCY(WEAK) */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (20001) and (con_id > 1000 or con_id = 1) and class < 1000If you use OceanBase Database V4.0 or later, execute the following statement:
select /* MONITOR_AGENT */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (20001) and (con_id > 1000 or con_id = 1) and class < 1000