Re: [Exim] Some performance notes

Michael Brutman wrote:
>
> I'm unclear about split_spool_directory - is then intention to split the
> spool files across multiple hard drives, or is there a bottleneck in the
> filesystem code that limits concurrent accesses to the directory. (i.e.:
> Is it disk performance or a kernel locking problem that this setting gets
> around.)

split_spool_directory creates a directory hirarchy in the SPOOL/input/
directory, this helps in cases were many queue-files are created, as
some file-systems (ext2 is one of them) have problems with BIG directories.

> NSCD was used.

fine

> OpenLDAP "opened up" to use 33 threads on a busy system. I'm not sure if
> this was the problem, or if it was the rapid creation and destruction of
> processes when doing deliveries. (The kernel profiling work tells me the
> processes are a problem, but the kernel profiling can't see the user-mode
> bottlenecks, so they may be there as well.)

Every new exim-process that queries the ldap server will open a new
connection to it. So it's good to reduce the queries a little bit :)

ciao