Re: How to raise the open file descriptor limit for slapd?

[matthew sporleder <msporleder@gmail.com>]

You should be able to set ulimit values in your daemon's init script,
or set them system-wide.

_Matt

On 10/4/05, David Landgren <david@landgren.net> wrote:
> List,
>
> I have a fairly heavily used openldap-2.2.28 server in production and I
> am running into the 1024 fd descriptor limit. From time to time I get
>
>    1024 beyond descriptor table limit 1024
>
> on my syslog host. I found the following message in the archives:
>
> http://www.openldap.org/lists/openldap-software/200303/msg00858.html
> beyond descriptor table size error
>
> One of the suggestions was to keep an eye on open sockets. So I wrote
> the following script:
>
> netstat --inet --numeric-hosts --numeric-ports --numeric-users \
>      | tail +3          \
>      | awk '{print $6}' \
>      | sort             \
>      | uniq -c          \
>      | awk '{n+=$1; print} END {printf("%7d\n", n)}'
>
> which I run every five minutes. Within minutes of restarting slapd this
> morning, I was seeing:
>
> Tue Oct  4 09:09:02 CEST 2005
>       40 CLOSE_WAIT
>      242 ESTABLISHED
>       60 TIME_WAIT
>      342
> Tue Oct  4 09:14:03 CEST 2005
>       37 CLOSE_WAIT
>      293 ESTABLISHED
>       65 TIME_WAIT
>      395
> Tue Oct  4 09:19:03 CEST 2005
>       46 CLOSE_WAIT
>      335 ESTABLISHED
>       37 TIME_WAIT
>      418
>
> Now during the heavy activity during the morning I see
>
> Tue Oct  4 11:29:11 CEST 2005
>      131 CLOSE_WAIT
>      664 ESTABLISHED
>        2 FIN_WAIT1
>        1 FIN_WAIT2
>       32 TIME_WAIT
>      830
> Tue Oct  4 11:34:12 CEST 2005
>      130 CLOSE_WAIT
>      647 ESTABLISHED
>        2 FIN_WAIT1
>       14 TIME_WAIT
>      793
> Tue Oct  4 11:39:12 CEST 2005
>      131 CLOSE_WAIT
>      660 ESTABLISHED
>        2 FIN_WAIT1
>        1 FIN_WAIT2
>       40 TIME_WAIT
>      834
> Tue Oct  4 11:44:13 CEST 2005
>      130 CLOSE_WAIT
>      659 ESTABLISHED
>        2 FIN_WAIT1
>       17 TIME_WAIT
>      808
>
>
> So the close_wait values are getting higher, and I may be able to tune
> this down by clamping the idle_timeout setting, but as it is, I don't
> think I have enough headroom.
>
> One of the suggestions was to increase FD_SETSIZE, which seems to me to
> be the right thing to do, but I'm not quite sure what the recommended
> practice is. In the CHANGES file I see a mention of OPENLDAP_FD_SETSIZE
> but a quick grep through the source does not turn up any other reference.
>
> Do I define this as an environment variable, or should I define
> CFLAGS=-DOPENLDAP_FD_SETSIZE=2048 , or something else?
>
> Your suggestions are appreciated,
> David
> --
> "It's overkill of course, but you can never have too much overkill."
>