Re: Block-level CRC checks

Gregory Stark escribió:
> Alvaro Herrera <alvherre@commandprompt.com> writes:
> 
> > Jonah H. Harris escribió:
> >> Now, in the case where hint bits have been updated and a WAL record is
> >> required because the buffer is being flushed, requiring the WAL to be
> >> flushed up to that point may be a killer on performance.  Has anyone
> >> tested it?
> >
> > I didn't measure it but I'm sure it'll be plenty slow.
> 
> How hard would it be to just take an exclusive lock on the page when setting
> all these hint bits?

I guess it will be intolerably slow then.  If we were to say "we have
CRC now, but if you enable it you have 1% of the performance" we will
get laughed at.

-- 
Alvaro Herrera                                http://www.CommandPrompt.com/
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