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AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
System administrationThese topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL OneDB™ database servers.
Performance GuideThe HCL OneDB™ Performance Guide describes how to configure and operate your HCL OneDB™ database server to improve overall system throughput and to improve the performance of SQL queries.
Effect of configuration on memory utilizationThe combination of operating-system and HCL OneDB™ configuration parameters can affect memory utilization.
Memory latchesThe database server uses latches to control access to shared memory structures such as the buffer pool or the memory pools for the SQL statement cache. You can obtain statistics on latch use and information about specific latches. These statistics provide a measure of the system activity.
Monitoring latches with command-line utilitiesYou can obtain information about latches by running onstat -p or onstat -s.
Monitoring latches with onstat -pRun onstat -p to obtain the values in the lchwaits field. This field stores the number of times that a thread was required to wait for a shared-memory latch.

Monitoring latches with onstat -p

Run onstat -p to obtain the values in the lchwaits field. This field stores the number of times that a thread was required to wait for a shared-memory latch.

Partial onstat -p output showing the lchwaits field shows an excerpt of sample onstat -p output that shows the lchwaits field.

Figure 1: Partial onstat -p output showing the lchwaits field

...
ixda-RA  idx-RA   da-RA   logrec-RA    RA-pgsused lchwaits
5        0        204      0           148        12

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