Re: pgsql-server: Add: > > * Allow buffered WAL writes

On Sat, 14 Aug 2004, Tom Lane wrote:

> Bruce Momjian <pgman@candle.pha.pa.us> writes:
>> Many databases offer this feature.  The submitter asked for it,
>
> Actually he didn't --- AFAICS you misinterpreted the thread completely.
> The original suggestion was that we might be able to exploit a
> transactional filesystem to improve performance *without* sacrificing
> any correctness guarantees.  Delayed fsync has nothing to do with that.
>
> (I'm dubious whether there's any performance improvement to be had that
> would be worth the code uglification involved, since we're surely not
> going to *require* a transactional filesystem and so two very different
> code paths seem to be needed.  But it's at least something to think about.)

Just to expand on the 'dubiousness' ... remember awhile back when I worked
through the 'no-WAL' version of PostgreSQL to test loading a database with
WAL disabled?  The performance improvements on loading a database weren't
enough, I seem to recall, to warrant getting rid of WAL altogether ... so
I can't see 'delayed WAL' being faster then 'no WAL' ...


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Email: scrappy@hub.org           Yahoo!: yscrappy              ICQ: 7615664