From: Kristian Nielsen Date: June 15 2009 10:06am Subject: Re: mtr2 CPU detection for MacOS X List-Archive: http://lists.mysql.com/internals/36909 Message-Id: <87ws7d4xqo.fsf@knielsen-hq.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Stewart Smith writes: > Really simple patch to get the CPU count out of an OSX box for automatic > --parallel setting for mtr2. Actually, in my experience, --parallel gives huge speedups even on a single-processor machines. Most of the time seems to be spent in sleep(), not in burning CPU :-(. So I would think it makes more sense to set parallelism on available memory? (Assuming running in ram disk, if not disk trashing becomes the limit under higher --parallel values). But maybe this is different in Drizzle, haven't run Drizzle tests in a while. - Kristian.