Re: wal_buffers

On Sun, Feb 19, 2012 at 9:46 AM, Euler Taveira de Oliveira
<euler(at)timbira(dot)com> wrote:
> On 19-02-2012 02:24, Robert Haas wrote:
>> I have attached tps scatterplots.  The obvious conclusion appears to
>> be that, with only 16MB of wal_buffers, the buffer "wraps around" with
>> some regularity
>>
> Isn't it useful to print some messages on the log when we have "wrap around"?
> In this case, we have an idea that wal_buffers needs to be increased.

I was thinking about that. I think that what might be more useful
than a log message is a counter somewhere in shared memory. Logging
imposes a lot of overhead, which is exactly what we don't want here,
and the volume might be quite high on a system that is bumping up
against this problem. Of course then the question is... how would we
expose the counter value?

--
Robert Haas
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