Re: (ITS#4409) (back-ldap?) livelock in slapd

[ando@sys-net.it]

On Thu, 2006-02-16 at 21:42 +0000, richton@nbcs.rutgers.edu wrote:
> Full_Name: Aaron Richton
> Version: 2.3.19
> OS: Solaris 9
> URL: ftp://ftp.openldap.org/incoming/
> Submission from: (NULL) (128.6.31.135)
> 
> 
> About 20 minutes after the back-ldap "retry" situation described in my post to
> openldap-software (sorry for no link but it's not in the archive yet), slapd
> started gunning the CPU with yield()s. See
> https://www.nbcs.rutgers.edu/~richton/richton-20060216-trace.txt for backtrace
> from gcore(1) when it was gunning CPU. I also have an image from using gcore at
> 16:11 (while I was waiting for the retry to take place, when service was
> degraded) and from after I sent a kill -INT (which was insufficient; I had to
> kill -9 the process).

Looks like all your threads are stuck with the same connection, all
waiting for one of them to succeed in binding.  There appears to be a
deadlock condition, which should be solved somehow.
Basically, ldap_back_getconn() should not let a connection be acquired
before it becomes bound.  Simply giving up the connection in that loop
would cause some operations to temporarily fail, which may not be the
best solution.

p.




Ing. Pierangelo Masarati
Responsabile Open Solution
OpenLDAP Core Team

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