On Thu, Jan 13, 2011 at 6:02 PM, Josh Berkus <josh@agliodbs.com> wrote:
>
>> Depends what people want to do. We could make the default "0kB", and
>> define that to mean "auto-tune", or we could remove the parameter
>> altogether. I think I was envisioning the latter, but if people are
>> hesitant to do that we could do the former instead.
>
> Unfortunately, we might still need a manual parameter for override
> because of the interaction between wal_buffers and
> synchronous_commit=off, since it sets the max size of the unflushed data
> buffer. Discuss?
Do we have any evidence there's actually a problem in that case, or
that a larger value of wal_buffers solves it? I mean, the background
writer is going to start a background flush as quickly as it can...
> And the "auto" setting should be -1, not 0kB. We use -1 for "use
> default" for several other GUCs.
No can do. Gotta have things in the same units.
> Other than that, I think Greg's numbers are fine, and strongly support
> having one less thing to tune.
OK.
--
Robert Haas
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