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Re: Threads Backload

Bill MacAllister writes:
> In looking at some load issues on our servers we have starting recording 
> some cn=Monitor counters for analysis.  In particular we would like to 
> understand what cn=Backload,cn=Threads,cn=Monitor contains.  On our servers 
> we have threads set to 8 and we have seen maximum backload values of 56. 
> Does this means there are 56 connections waiting for an execution thread?

Someone else could give a better answer but...

No, it's the number of unfinished tasks submitted to the thread pool.
Each LDAP operation is submitted as a separate task - i.e. a C function
call to be performed.  With your numbers, 8 or fewer are active and the
remaining 48 are waiting for a thread to pick them up and run them.

Note that some other tasks are also submitted to the thread pool, I
don't remember quite which ones.  Listening for new connections, reading
from and closing a connection, depending on how slapd is compiled.  "Run
queue" tasks, which I don't remember what are.  Replication, maybe.