Re: (ITS#7222) Slapd hangs on high load

[hrvoje.habjanic@zg.t-com.hr]

On 03.04.2012 17:41, Howard Chu wrote:
>>
>> So, am i doing something wrong or openldap is...?
>
>
> Looks like your glibc malloc is deadlocked. A Centos bug, not an
> OpenLDAP bug.
>
> In the trace, you could confirm this in gdb with:
>     thread 13
>     frame 3
>     print *mutex
>
> most likely the "owner" field of this mutex will be 1502, which
> corresponds to thread 17, which is waiting for a lock inside libc
> malloc/free.
>
> You may be able to avoid this bug by using an alternate malloc
> library, such as Google tcmalloc.
>

Hi.

Thanx for inside info ... :-)

And sorry that i was unable to provide more info - core dump alone is
16gb! Also, small sidenote - when this "hang" happens, it only affects
existing connections - i'm attacking it with two procesess, each 4
connection. New searches using ldapsearch work fine ...

And correction for typo - by "high load" i wrote (1-2 req/sec) -
actually it should write 1-2k reg/sec ...

What is interesting regarding this, that this "problem" goes back to
db-4.7 and openldap-2.4.23 (provided with centos) ...

I'll try alternate malloc and report back ...

H.