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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 Informix® database servers.
Performance GuideThe Informix® Performance Guide describes how to configure and operate your HCL Informix® 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 Informix® 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 -sRun onstat -s to obtain general latch information. The output includes the userthread column, which lists the address of any user thread that is waiting for a latch.

Monitoring latches with onstat -s

Run onstat -s to obtain general latch information. The output includes the userthread column, which lists the address of any user thread that is waiting for a latch.

You can compare this address with the user addresses in the onstat -u output to obtain the user-process identification number.

onstat -s output shows sample onstat -s output.

Figure 1: onstat -s output

...
Latches with lock or userthread set
name     address  lock wait userthread
LRU1     402e90   0    0        6b29d8
bf[34]   4467c0   0    0        6b29d8
...

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