Re: Attempt to consolidate reading of XLOG page

On 2019-Nov-22, Antonin Houska wrote:

> I thought that in [1] you try discourage me from using pg_pread(), but now it
> seems to be the opposite. Ideally I'd like to see no overhead added by my
> patch at all, but the code simplicity should matter too.

FWIW I think the new code is buggy because it doesn't seem to be setting
ws_off, so I suppose the optimization in ReadPageInternal to skip
reading the page when it's already the page we have is not hit, except
for the first page in the segment.  I didn't verify this, just my
impression while reading the code.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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