Re: RE24 (2.4.15) slapd consuming large amounts of CPU
Hi Quanah,
I have some question about Debian builds of openldap. Maybe you can
answer any.
--On Wednesday, March 04, 2009 3:30 PM -0500 John Morrissey
<jwm(a)horde.net>
wrote:
> On Wed, Mar 04, 2009 at 12:13:49PM -0800, Quanah Gibson-Mount wrote:
>> --On Wednesday, March 04, 2009 1:55 PM -0500 John Morrissey
>>
>> <jwm(a)horde.net> wrote:
>> > After a few hours of uptime, slapd suddenly begins consuming
>> > enormous amounts of CPU (a three- to four-fold increase over
>> > less than a few minutes, and is sustained until slapd is
>> > restarted).
>>
>> Interseting. I've seen this sort of CPU usage issue with OpenLDAP
>> 2.3/BDB4.2.52 on Ubuntu 8. Do you know how BDB 4.7 was built?
>> I.e., specifically, did it have the:
>>
>> --enable-posixmutexes --with-mutex=POSIX/pthreads
>>
>> options enabled?
>
> It's the Debian packaging for BDB 4.7 (only available in sid, but
> it's a simple rebuild to backport to lenny). They do *not* appear
> to pass any mutex-related options to ./configure.
Yeah, that's a major problem in using Debian's builds of BDB. You
want those options sent to configure when using BDB on Linux NPTL
systems.
I try to reconfigure and backport the bdb4.7 package to lenny. The above
mentioned mutex settings are now added.
The config statement in debian/rules is now:
CONFIGURE_SWITCHES = --prefix=/usr \
--mandir=\$${prefix}/share/man \
--localstatedir=/var \
--sysconfdir=/etc \
--libexecdir=/usr/lib \
--enable-cxx \
--enable-compat185 \
--enable-rpc \
--enable-tcl \
--with-tcl=/usr/lib/tcl8.5 \
--enable-test \
--enable-posixmutexes \
--with-mutex=POSIX/pthreads
The build was successfull. Some warnings in the java-packages about
unused variables. I believe that doesn't matter.
>> Also, are you using a shared memory key?
How can I
realize that?
>> I've found that has a
>> significant (positive) impact with BDB 4.7 on linux boxes.
>
> We are not. Thanks, I'll give that a try.
No prob. :) You may have to adjust some settings in sysctl to do it.
;)
Can you tell me, what I should adjust in sysctl.
I have seen that the Debian package maintainers have modified the schema
and ldif files of openldap. So, when I want to rebuild openldap, I
suggest that I must flag the build as non-free. At least in Debian
terminology.
They use gnutls as ssl package. I've found some bad mails about gnutls
code quality. I believe that was in spring 2008. Should I build with
openssl instead ?
--Quanah
--
Quanah Gibson-Mount
Principal Software Engineer
Zimbra, Inc
--------------------
Zimbra :: the leader in open source messaging and collaboration
--
Gruss
Harry Jede