[Kolab-devel] Re: OpenLDAP performance issues

[Dieter Kluenter]

Hi Bernhard,

Bernhard Reiter <bernhard at intevation.de> writes:

> Hi Dieter,
>
> first thanks for giving us a hand here with OpenLDAP,
> I really appreciate it!
>
> On Sunday 22 May 2005 21:58, Dieter Kluenter wrote:
>> Martin Konold <martin.konold at erfrakon.de> writes:
>
>> BTW we observed the hangs independent of the write traffic!
>>
>> Can you present some more details?
>> - database size
>
> E.g.  onn fresh Kolab Servers.
> The database is very small, well under 50 objects.
>
>> - configuration options
> Here are some that I guess are relevant:
>
[...]

> several access permissions, one replica.
>
> DB_CONFIG has
> set_cachesize   0       26214400        1
> set_tmp_dir /dev/shm
>
>> - search strings
>
> The regular kolab ones.
> Binds with nobody and a long password (30 characters).
>
>> - search frequency
>
> I had those hangs wheren there have not been many searches around
> and one f the first write operations by the kolab webadmin, caused the hang.
> The hang is caused by write operations, I have not seen other cases.
>
>> If you have added a 'database monitor' entry to slapd.conf, what is
>> the output of
>> ldapsearch -x -H ldap://my.host -b cn=waiters,cn=monitor -s sub +
>> ldapsearch -x -H ldap://my.host -b cn=operations,cn=monitor -s sub +
>>
>> Please note that all attributes of cn=monitor are operational, the +
>> is the wildcard for operational attributes.
>
> I still have to do this to gather more data.
> Anything that you can already say?
> Could this be related to othe kernel or the filesystems?

I have never experienced such problems but it seems that openldap is
compiled --without-threads, as no libpthread or any other posix thread
is included as there is no appropriate library in /kolab/lib, could
you please check this?

,----[ kolab slapd ]
| marin:/kolab/libexec/openldap # ldd slapd
|         linux-gate.so.1 =>  (0xffffe000)
|         libcrypt.so.1 => /lib/libcrypt.so.1 (0x40029000)
|         libresolv.so.2 => /lib/libresolv.so.2 (0x4005b000)
|         libnsl.so.1 => /lib/libnsl.so.1 (0x4006f000)
|         libc.so.6 => /lib/tls/libc.so.6 (0x40085000)
|         /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)
`----

Just in comparison to an installation an an other box

,----[ rubin slapd ]
| rubin:/usr/local/libexec> ldd slapd
|         libdb-4.3.so => /usr/lib64/tls/libdb-4.3.so (0x00002aaaaabc2000)
|         libsasl2.so.2 => /usr/lib64/libsasl2.so.2 (0x00002aaaaadb1000)
|         libssl.so.0.9.7 => /usr/lib64/libssl.so.0.9.7 (0x00002aaaaaec9000)
|         libcrypto.so.0.9.7 => /usr/lib64/libcrypto.so.0.9.7 (0x00002aaaaaffe000)
|         libresolv.so.2 => /lib64/libresolv.so.2 (0x00002aaaab231000)
|         libpthread.so.0 => /lib64/tls/libpthread.so.0 (0x00002aaaab346000)
|         libc.so.6 => /lib64/tls/libc.so.6 (0x00002aaaab45b000)
|         libdl.so.2 => /lib64/libdl.so.2 (0x00002aaaab681000)
|         /lib64/ld-linux-x86-64.so.2 (0x00002aaaaaaab000)
`----

-Dieter

-- 
Dieter Klünter | Systemberatung
http://www.dkluenter.de
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