Re: Question about concurrent synchronous and asynchronous commits

Ok given your response, this is my understanding of how the WAL works:

When you begin a transaction, all your changes write to the in-memory WAL
buffer, and that buffer flushes to disk when:
a) Somebody commits a synchronous transaction
b) The WAL buffer runs out of space

Please correct me if I'm wrong.

-Dan

On Wed, Jan 12, 2011 at 12:32 PM, Vick Khera <vivek(at)khera(dot)org> wrote:

> On Wed, Jan 12, 2011 at 12:03 AM, Dan Birken <birken(at)gmail(dot)com> wrote:
> > If I commit asynchronously and then follow that with
> a synchronous commit,
> > does that flush the asynchronous commit as well?
>
> I'm pretty sure it does, because it has to flush the write-ahead log
> to disk, and there's only one. You can think of it as getting the
> flush for free from the first transaction, since the single flush
> covered the requirements of both transactions.
>
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