Re: PostgreSQL as a local in-memory cache - Mailing list pgsql-performance

From Tom Lane
Subject Re: PostgreSQL as a local in-memory cache
Date
Msg-id 20972.1277832454@sss.pgh.pa.us
Whole thread Raw
In response to Re: PostgreSQL as a local in-memory cache  (Bruce Momjian)
Responses Re: PostgreSQL as a local in-memory cache  (Bruce Momjian)
List pgsql-performance
Bruce Momjian <> writes:
>>> I asked on IRC and was told it is true, and looking at the C code it
>>> looks true. ?What synchronous_commit = false does is to delay writing
>>> the wal buffers to disk and fsyncing them, not just fsync, which is
>>> where the commit loss due to db process crash comes from.

>> Ah, I see.  Thanks.

> I am personally surprised it was designed that way;  I thought we would
> just delay fsync.

That would require writing and syncing to be separable actions.  If
you're using O_SYNC or similar, they aren't.

            regards, tom lane

pgsql-performance by date:

Previous
From: Bruce Momjian
Date:
Subject: Re: PostgreSQL as a local in-memory cache
Next
From: Bruce Momjian
Date:
Subject: Re: PostgreSQL as a local in-memory cache