I wrote:
> (BTW, in case you can't tell from the drift of my questions, I've
> separated the patch into "add background wal writer" and "add async
> commit", and am working on the first half.)
I've committed the first half of that. Something that still needs
investigation is what the default wal_writer_delay should be. I left
it at 200ms as submitted, but in some crude testing here (just running
the regression tests and strace'ing the walwriter) it seemed that I had
to crank it down to 10ms before the walwriter was really doing the
majority of the wal-flushing work.
regards, tom lane