Re: Problem with data corruption and psql memory usage

Hello Tom,

Late answer, but answer :-) :
Finally, it was a very strange hardware problem, where a very small part
of RAM was defect but kernel never crashed.

I had also a very strange behavior when verifying rpm packages with rpm
-V. First I had the harddisk under suspicion. But then I flushed the OS caches:
echo 3 > /proc/sys/vm/drop_caches
and rpm -V was correct. => RAM issue.

A memtest86+ showed very fast a defect RAM.

So PostgreSQL didn't have any issue :-)

Ciao,
Gerhard

--
http://www.wiesinger.com/

On Wed, 9 May 2007, Gerhard Wiesinger wrote:

> Hello Tom!
>
> I don't think this is a hardware problem. Machine runs 24/7 for around 4
> years without any problems, daily backup with GBs of data to it, uptimes to
> the next kernel security patch, etc.
>
> The only problem I could believe is:
> I'm running the FC7 test packages of postgresql in FC6 and maybe there is a
> slight glibc library conflict or any other incompatibility.
>
> Ciao,
> Gerhard
>
> --
> http://www.wiesinger.com/
>
>
> On Wed, 9 May 2007, Tom Lane wrote:
>
>> Gerhard Wiesinger <lists(at)wiesinger(dot)com> writes:
>>> LOG: could not fsync segment 0 of relation 1663/16386/42726: Input/output
>>> error
>>
>> [ raised eyebrow... ] I think your machine is flakier than you believe.
>> This error is particularly damning, but the general pattern of weird
>> failures all over the place seems to me to fit the idea of hardware
>> problems much better than any other explanation. FC6 and PG 8.2.3 are
>> both pretty darn stable for most people, so there's *something* wrong
>> with your installation, and unstable hardware is the first thing that
>> comes to mind.
>>
>> regards, tom lane
>>
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