On Sat, 4 Jan 2003, Christopher Kings-Lynne wrote: > Also remember that in even well developed OS's like FreeBSD, all a > process's threads will execute only on one CPU.
I would say that that's not terribly well developed. Solaris will split a single processes' threads over multiple CPUs, and I expect most other major vendors Unixes will as well. In the world of free software, the next release of NetBSD will do the same. (The scheduler activations system, which support m userland to n kernel threads mapping, was recently merged from its branch into NetBSD-current.) >From my experience, threaded sorts would be a big win. I managed to shave index generation time for a large table from about 12 hours to about 8 hours by generating two indices in parallel after I'd added a primary key to the table. It would have been much more of a win to be able to generate the primary key followed by other indexes with parallel sorts rather than having to generate the primary key on one CPU (while the other remains idle), wait while that completes, generate two more indices, and then generate the last one . cjs -- Curt Sampson <[EMAIL PROTECTED]> +81 90 7737 2974 http://www.netbsd.org Don't you know, in this new Dark Age, we're all light. --XTC ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/users-lounge/docs/faq.html
