This topic describes performance metrics related to the IO time-consuming in an OceanBase cluster. You can specify a statistical period to query statistics about the IO time-consuming in a single zone or on a single OBServer of an OceanBase cluster.
ssstore_read
Definition
The average time consumed by each SSStore read in the cluster in the specified statistical period.
Description
| Metric | Metric field name | Unit |
|---|---|---|
| ssstore_read | io_read_rt | μs |
Calculation expression
sum(rate(ob_sysstat{stat_id=“60001”,@LABELS}[@INTERVAL])) by (@GBLABELS) / sum(rate(ob_sysstat{stat_id=“60000”,@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$sysstat where stat_id IN (60000, 60001) and (con_id > 1000 or con_id = 1) and class < 1000If you use OceanBase Database V4.0 or later, execute the following statement:
select /* MONITOR_AGENT */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (60000, 60001) and (con_id > 1000 or con_id = 1) and class < 1000
ssstore_write
Definition
The average time consumed by each SSStore write in the cluster in the specified statistical period.
Description
| Metric | Metric field name | Unit |
|---|---|---|
| ssstore_write | io_write_rt | μs |
Calculation expression
sum(rate(ob_sysstat{stat_id=“60004”,@LABELS}[@INTERVAL])) by (@GBLABELS) / sum(rate(ob_sysstat{stat_id=“60003”,@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$sysstat where stat_id IN (60003, 60004) and (con_id > 1000 or con_id = 1) and class < 1000If you use OceanBase Database V4.0 or later, execute the following statement:
select /* MONITOR_AGENT */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (60003, 60004) and (con_id > 1000 or con_id = 1) and class < 1000
clog_read
Definition
The number of clog reads in a cluster per second in the specified statistical period.
Description
| Metric | Metric field name | Unit |
|---|---|---|
| clog_read | clog_io_read_rt | μs |
Calculation expression
sum(rate(ob_sysstat{stat_id=“80009”,@LABELS}[@INTERVAL])) by (@GBLABELS) / sum(rate(ob_sysstat{stat_id=“80007”,@LABELS}[@INTERVAL])) by (@GBLABELS)
SQL statements for metric collection
If you use OceanBase Database V4.0 or later, execute the following statement:
select /* MONITOR_AGENT */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (80007, 80009) and (con_id > 1000 or con_id = 1) and class < 1000
clog_write
Definition
The number of clog writes in a cluster per second in the specified statistical period.
Description
| Metric | Metric field name | Unit |
|---|---|---|
| clog_write | clog_io_write_rt | μs |
Calculation expression
sum(rate(ob_sysstat{stat_id=“80003”,@LABELS}[@INTERVAL])) by (@GBLABELS) / sum(rate(ob_sysstat{stat_id=“80001”,@LABELS}[@INTERVAL])) by (@GBLABELS)
SQL statements for metric collection
If you use OceanBase Database V4.0 or later, execute the following statement:
select /* MONITOR_AGENT */ con_id tenant_id, stat_id, value from v$sysstat where stat_id IN (80001, 80003) and (con_id > 1000 or con_id = 1) and class < 1000