Symas OpenLDAP Knowledge Base

slapd Threads Warning

In some occurrences, when using slapd on start-up, the following error message can occur:

    /opt/.../slapd.conf: line 60: warning, threads=N larger than twice the default (2*<max_worker_threads>=NN); YMMV

This message states that the default number of CPU threads (being two) is less than the amount being used at the time. The purpose of warning is to communicate to the user that using more than two may decrease the speed of the program. However, this only pertains to small, older machines and does not pertain to newer machines with the ability to handle more.

In the occurrence of this warning, it is important to keep in mind the capabilities of your machine. In order to maintain the best possible speed of your machine, you may want to pay attention to the amount of reliance on slapd and not other programs.

NOTE: All programs will come with warnings for their intended purpose. It is up to the user to review these preset warnings and choose to bypass if needed. In this scenario, someone with a larger machine capable of computing with 48 threads does not need to keep in mind the warning of 2 or more threads that slapd is equipped to warn about.

Since slapd is not equipped to read the system’s hardware configuration and analyze whether the system is able to process this amount, the best practice is to rely on ‘sysadmin’ to take on that job.