Re: ERROR: invalid memory alloc request size, and others

Jonathan Hedstrom wrote:
> Tom Lane wrote:
>> Scott Marlowe <smarlowe(at)g2switchworks(dot)com> writes:
>>
>>> Also, schedule some maintenance window for your server to run memtest86
>>> and possibly something to check for bad blocks on your drives.
>>>
>> +1 ... I have not seen any instance of "invalid page header" that could
>> be traced to a Postgres bug. The cases I've been able to study all
>> seemed to involve either flaky hardware or kernel-level bugs (such as
>> dumping a fragment of some unrelated file into a Postgres table :-()
>>
>> regards, tom lane
>>
> Since it sounds like this is either a hardware or a kernel issue, we're
> wondering if our downtime would be better spent rebooting to the
> standard FC6 kernel, or trying some of the aforementioned hardware tests...
>
> We are running a xen kernel: 2.6.18-1.2798.fc6xen

This is the base Xen kernel from the FC 6 release. There have been 3
updates released since then (most recently 01-Jan). I see a number of
Xen fixes in the changelog, and I know that the major factor in the
slippage of the FC 6 release was getting Xen into the distro -- so I
would definitely expect some Xen bugs in the initial cut from the release.

Simplest advice I can think of: if you don't need Xen, go back to the
stock (albeit most recent update) kernel. If you do need Xen, try the
most recent update of the stock kernel anyway. If the problems persist,
you've at least eliminated one variable. If they go away, you've got
the culprit.

Note that I don't use Xen, so I'm not completely up-to-date... Last I
knew there were issues preventing Xen from being included in the
upstream Linux kernel (vendors are patching it in individually), and
that speaks volumes as to the "newness" of the technology.

Andrew