Re: [HACKERS] increasing the default WAL segment size

On 3 January 2017 at 16:24, Robert Haas <robertmhaas@gmail.com> wrote:
> On Jan 3, 2017 at 11:16 AM, Simon Riggs <simon@2ndquadrant.com> wrote:
>> On 3 January 2017 at 15:44, Robert Haas <robertmhaas@gmail.com> wrote:
>>> Yeah.  I don't think there's any way to get around the fact that there
>>> will be bigger latency spikes in some cases with larger WAL files.
>>
>> One way would be for the WALwriter to zerofill new files ahead of
>> time, thus avoiding the latency spike.
>
> Sure, we could do that.  I think it's an independent improvement,
> though: it is beneficial with or without this patch.

The latency spike problem is exacerbated by increasing file size, so I
think if we are allowing people to increase file size in this release
then we should fix the knock-on problem it causes in this release
also. If we don't fix it as part of this patch I would consider it an
open item.

-- 
Simon Riggs                http://www.2ndQuadrant.com/
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