Red Hat Directory Server 7.1 Performance Tuning and Sizing Guidelines

lower. Setting the value to 0 turns off the cache autosizing and uses the normal nsslapd-cachememsize and nsslapd-dbcachesize attributes.

Entry DN:

cn=config,cn=ldbm database,cn=plugins,cn=config

Valid Range:

0 (turns cache autosizing off) to 100

Default Value:

0

Syntax:

Integer

Example:

nsslapd-cache-autosize: 80

If you set nsslapd-cache-autosizeto a non-zero value between 0 and 100, RHDS will override the nsslapd-cachememsizeand nsslapd-dbcachesizewith a value calculated based on the amount of free memory at the time RHDS starts up. This is often not preferable as free memory might fluctuate from time to time depending on usage of the system.

Logging

Directory Server provides three types of logs to help you better manage your directory and tune performance. These logs include:

•Access log: The access log contains detailed information about client connections to the directory. It provides beneficial troubleshooting information. Access logging is enabled by default.

•Error log: The error log contains detailed messages of errors and events the directory experiences during normal operations. Error logging is enabled by default.

•Audit log: The audit log contains detailed information about changes made to each database as well as to server configuration. By default, audit logging is disabled.

In a typical production environment, access log should be turned off, otherwise it will cause excessive disk I/O despite buffering which will affect performance. For customers who want to have access log turned on, they can put the access log file on a separate physical disk to improve the performance. In the performance test environment, turning off the access log can increase the search throughput by 4%. Please see table 6.

Performance Measurements

This section describes performance testing for Red Hat Directory Server version 7.1 under controlled environment with databases containing 100, 10K, 100K, 250K, 500K, 1M, 5M∗ and 10M∗ entries. The directory entries were inetorgPerson entries generated by DirMark. Performance data was measured for exact search on CN only.

Purpose

•Find out how number of CPUs affects the performance.

•Find out how threadnumbers affects the performance.

•Find out how dbcachesize affects the performance.

•Find out how cachememsize and cachesize affect the performance.

•Find out how logging affects the performance.

•Find out the performance differences between a SSL connection and a non-SSL connection.

Test Result

Data collection 1: (Different Number of CPUs)

This set of data is collected to help us understand the performance differences between different numbers of CPUs.

•#of entries: 100k entries

∗See Appendix C and Appendix D for detail

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