Re: Hot Backup with rsync fails at pg_clog if under load

On Wed, Oct 26, 2011 at 12:16 PM, Florian Pflug <fgp@phlo.org> wrote:

>> Chris' clog error was caused by a file read error. The file was
>> opened, we did a seek within the file and then the call to read()
>> failed to return a complete page from the file.
>>
>> The xid shown is 22811359, which is the nextxid in the control file.
>>
>> So StartupClog() must have failed trying to read the clog page from disk.
>
> Yep.
>
>> That isn't a Hot Standby problem, a recovery problem nor is it certain
>> its a PostgreSQL problem.
>
> It's very likely that it's a PostgreSQL problem, though. It's probably
> not a pilot error since it happens even for backups taken with pg_basebackup(),
> so the only explanation other than a PostgreSQL bug is broken hardware or
> a pretty serious kernel/filesystem bug.

The way forwards here is for someone to show the clog file that causes
the error and find out why the call to read() fails.

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