Re: Fail to start Postgres on Ubuntu kernel 2.6.28-15-generic

2009/9/8 Markus Pscheidt <markus(dot)pscheidt(at)gmail(dot)com>

>
> Hello,
>
> while on Ubuntu kernel 2.6.28-14-generic Postgres 8.3.7-1 works fine, it
> doesn't start on Ubuntu 9.04, kernel 2.6.28-15-generic. Following is the log
> output of 'sudo /etc/init.d/postgresql-8.3 start':
>
> Begin of log ==>
> 2009-09-08 08:17:52 CAT LOG: could not load root certificate file
> "root.crt": no SSL error reported
> 2009-09-08 08:17:52 CAT DETAIL: Will not verify client certificates.
> 2009-09-08 08:17:52 CAT FATAL: could not create shared memory segment:
> Invalid argument
> 2009-09-08 08:17:52 CAT DETAIL: Failed system call was shmget(key=5432001,
> size=38207488, 03600).
> 2009-09-08 08:17:52 CAT HINT: This error usually means that PostgreSQL's
> request for a shared memory segment exceeded your kernel's SHMMAX
> parameter. You can either reduce the request size or reconfigure the kernel
> with larger SHMMAX. To reduce the request size (currently 38207488 bytes),
> reduce PostgreSQL's shared_buffers parameter (currently 4096) and/or its
> max_connections parameter (currently 103).
> If the request size is already small, it's possible that it is less
> than your kernel's SHMMIN parameter, in which case raising the request size
> or reconfiguring SHMMIN is called for.
> The PostgreSQL documentation contains more information about shared
> memory configuration.
> <== end of log
>
> As a workaround it's possible to boot into the "old" kernel.
>
>

quite a common problem... see
http://www.postgresql.org/docs/8.3/static/kernel-resources.html

obvious question: what's in /proc/sys/kernel/shmmax ?

maybe your new kernel does not read sysctl settings properly?

--
Filip Rembiałkowski
JID,mailto:filip(dot)rembialkowski(at)gmail(dot)com
http://filip.rembialkowski.net/