Re: provider crash on high replication load

[Howard Chu <hyc@symas.com>]

Marc Patermann wrote:
> Hi,
>
> I have the following problem:
>
> On a sycrepl provider I have lots (100+) consumers in refresh and
> persist mode.
> After upgrading the provider from 2.3.x to 2.4.25 I can crash the server
> by a single mod on the root object of one database.
>
> Aug 15 14:18:37 trzs721boot kernel: [544888.798212] slapd[2861]:
> segfault at 0 ip 00007fbf89494522 sp 00007fbe8cfa7ca0 error 4 in
> slapd[7fbf8942c000+1b6000]
>
> I reproduced this on a test system, even with 2.4.26. The consumer are
> ldapsearch clients like this "-E!sync=rp/rid=xxx,csn= * +" on a single
> 2.4.25 machine. All SLES 11 SP1 64bit.
>
> Here is the gbd output.
>
> http://pastebin.com/6y83ZjqX
>
> I tried to create a core dump, but I could not get it work.
> I used this howto. The "top" example works, I get a core file for user
> ldap. With slapd it is not.
>
>
> Why does slapd crash here?

This looks like the same trace as ITS#6892, but that was already patched/fixed 
in 2.4.26. Need a bit more info from the crash. E.g.
	print *ss
	print *ss->s_op

--
  -- Howard Chu
  CTO, Symas Corp.           http://www.symas.com
  Director, Highland Sun     http://highlandsun.com/hyc/
  Chief Architect, OpenLDAP  http://www.openldap.org/project/