Re: BUG #4772: The server is hanging

gs wrote:
> The following bug has been logged online:
>
> Bug reference:      4772
> Logged by:          gs
> Email address:      gs@freenet.am
> PostgreSQL version: 8.3.1
> Operating system:   Fedora 9
> Description:        The server is hanging
> Details:
>
> Hello, the Linux server is going down, we don't know what is the problem -
> the kernel or PostgreSQL, here is some part from /var/log/messages, more
> detailed file can be downloaded from here:
> http://www.sendspace.com/file/7q4zwc
>
>
> Log:
>
> Apr 22 12:28:05 icon kernel: VFS: brelse: Trying to free free buffer
> Apr 22 12:28:05 icon kernel: ------------[ cut here ]------------
> Apr 22 12:28:05 icon kernel: WARNING: at fs/buffer.c:1215
> __brelse+0x28/0x2b() (Not tainted)
> Apr 22 12:28:05 icon kernel: Modules linked in: sunrpc ipv6 ipt_REJECT
>
....

that looks like a kernel fault to me,  nothing Postgres is doing should
cause the kernel to try to free an already free IO buffer.  this could
be triggered by a hardware problem, or a buggy kernel or kernel driver.

now, 8.3.1 is a early version in the 8.3 series (they are up to
8.3.7).     before persuing too many other avenues, I think I'd
temporarily disable postgres (boot up in safe mode, and disable the
postgres service via `chkconfig` or whatever), and make sure your fedora
9 is updated (yum update), and update postgres to 8.3.7.