Re: Analysis of ganged WAL writes - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Analysis of ganged WAL writes
Date
Msg-id 1976.1034088103@sss.pgh.pa.us
Whole thread Raw
In response to Re: Analysis of ganged WAL writes  ("Curtis Faith" <curtis@galtair.com>)
Responses Re: Analysis of ganged WAL writes  ("Curtis Faith" <curtis@galtair.com>)
List pgsql-hackers
"Curtis Faith" <curtis@galtair.com> writes:
> Successive writes would write different NON-OVERLAPPING sections of the
> same log buffer. It wouldn't make sense to send three separate copies of
> the entire block. That could indeed cause problems.

So you're going to undo the code's present property that all writes are
block-sized?  Aren't you worried about incurring page-in reads because
the kernel can't know that we don't care about data beyond what we've
written so far in the block?
        regards, tom lane


pgsql-hackers by date:

Previous
From: iafmgc@unileon.es
Date:
Subject: genetic query optimization
Next
From: Tom Lane
Date:
Subject: Re: Dirty Buffer Writing [was Proposed LogWriter Scheme]