On Fri, May 1, 2009 at 8:29 PM, PFC <lists@xxxxxxxxxx> 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 -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
