Re: Page Checksums + Double Writes

On Thu, Dec 22, 2011 at 8:42 AM, Florian Weimer <fweimer@bfk.de> wrote:
> * David Fetter:
>
>> The issue is that double writes needs a checksum to work by itself,
>> and page checksums more broadly work better when there are double
>> writes, obviating the need to have full_page_writes on.
>
> How desirable is it to disable full_page_writes?  Doesn't it cut down
> recovery time significantly because it avoids read-modify-write cycles
> with a cold cache?

It's way too late in the cycle to suggest removing full page writes or
code them. We're looking to add protection, not swap out existing
ones.

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