On Thu, Aug 29, 2013 at 10:55 PM, Fujii Masao <masao.fujii@gmail.com> wrote:
>> I suppose that the cost of the random I/O involved would
>> probably dominate just as with compress_backup_block = off. That said,
>> you've used an SSD here, so perhaps not.
>
> Oh, maybe my description was confusing. full_page_writes was enabled
> while running the benchmark even if compress_backup_block = off.
> I've not merged those two parameters yet. So even in
> compress_backup_block = off, random I/O would not be increased in recovery.
I understood it that way. I just meant that it could be that the
random I/O was so expensive that the additional cost of decompressing
the FPIs looked insignificant in comparison. If that was the case, the
increase in recovery time would be modest.
--
Peter Geoghegan