This topic describes monitoring metrics related to the MemStore within an OceanBase Database tenant. You can specify a statistical period to query the MemStore statistics in a single zone or on a single OBServer of an OceanBase Database tenant.
total
Definition
The MemStore size prepared for a tenant in the specified statistical period.
Description
| Metric | Metric field name | Unit |
|---|---|---|
| total | total_memstore_used | Byte |
Calculation expression
sum(ob_sysstat{stat_id="130001",@LABELS}) by (@GBLABELS) / 1048576
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$sysstat where stat_id IN (130001) and (con_id > 1000 or con_id = 1) and class < 1000If you use OceanBase Database V4.0 or later, execute the following statement:
select /* MONITOR_AGENT */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (130001) and (con_id > 1000 or con_id = 1) and class < 1000
active
Definition
The size of active MemStores in the specified statistical period.
Description
| Metric | Metric field name | Unit |
|---|---|---|
| active | active_memstore_used | Byte |
Calculation expression
sum(ob_sysstat{stat_id="130000",@LABELS}) by (@GBLABELS) / 1048576
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$sysstat where stat_id IN (130000) and (con_id > 1000 or con_id = 1) and class < 1000If you use OceanBase Database V4.0 or later, execute the following statement:
select /* MONITOR_AGENT */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (130000) and (con_id > 1000 or con_id = 1) and class < 1000
trigger
Definition
The MemStore size that triggers a major compaction in the specified statistical period. If the active MemStore size reaches this metric value, a major compaction is triggered.
Description
| Metric | Metric field name | Unit |
|---|---|---|
| trigger | major_freeze_trigger | Byte |
Calculation expression
sum(ob_sysstat{stat_id="130002",@LABELS}) by (@GBLABELS) / 1048576
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$sysstat where stat_id IN (130002) and (con_id > 1000 or con_id = 1) and class < 1000If you use OceanBase Database V4.0 or later, execute the following statement:
select /* MONITOR_AGENT */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (130002) and (con_id > 1000 or con_id = 1) and class < 1000
limit
Definition
The maximum MemStore size allowed to be used. If the value of the total_memstore_used metric field is greater than or equal to this metric value, data cannot be written to the MemStores.
Description
| Metric | Metric field name | Unit |
|---|---|---|
| limit | memstore_limit | Byte |
Calculation expression
sum(ob_sysstat{stat_id="130004",@LABELS}) by (@GBLABELS) / 1048576
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$sysstat where stat_id IN (130004) and (con_id > 1000 or con_id = 1) and class < 1000If you use OceanBase Database V4.0 or later, execute the following statement:
select /* MONITOR_AGENT */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (130004) and (con_id > 1000 or con_id = 1) and class < 1000