On Fri, May 1, 2009 at 8:29 PM, PFC <lists@peufeu.com> wrote:
> Roundtrips can be quite fast but they have a hidden problem, which is
> that everything gets serialized.
The client and server will serialize, but what usually matters most is
avoiding serializing against disk I/O--and that's why write-back
caching exists. There's still a benefit to pipelining (not everything
the db might need to read to complete the write will always be in
cache), but if everything was being serialized it'd be an order of
magnitude worse. That's why running each insert in a separate
transaction is so much slower; in that case, it *will* serialize
against the disk (by default).
--
Glenn Maynard