On Thu, Feb 17, 2011 at 4:38 PM, Mindaugas Rasiukevicius <rm...@netbsd.org> wrote: > Garrett Cooper <yaneg...@gmail.com> wrote: >> > >> > But what, that uses LWPCTL, are you actually supposed to be doing after >> > vfork()? Whack some environment variables and some globals -- maybe -- >> > then exec*(). What else is legitimate? >> > >> > If it doesn't slow down vfork, great, fix whatever. But vfork >> > performance really is critical. Look how much slower, for example, >> > FreeBSD builds the system than we do. vfork is a huge part of that. >> >> Hi Thor, >> Do you have performance metrics to back up your statement below >> about `FreeBSD build[ing] the system slower than we do' (paraphrased)? > > http://www.netbsd.org/~ad/5.0/img15.html > > Note: it uses the same toolchain (i.e. same make, gcc, etc). > > However, I suppose FreeBSD team is aware of these.
Mindaugas, Thanks for the details! I was looking for this (I couldn't find what Thor was referring to on the lists with a 45 or so minute Google search; it was turning up a lot of noise about Xen on the mailing lists :)..). It would be interesting to see how well FreeBSD fares now because 7.1 was before the ULE scheduler was setup as the default scheduler. A lot of work went into making that robust and scalable in 7.2 by jeffr@, jhb@, kris@, etc; one of the big announcements was made at a little before 7.0-RELEASE [1] and at MeetBSD 2008 [2] by kris@ when he was still actively working with the project :/... Things also improved again with scaling in FreeBSD 8.x, and there's work in the pipeline for 9.0-RELEASE to get rid of vm-locking which seems to have qualitatively yielded performance gains on the 2 workstations and 1 server I have FreeBSD CURRENT installed on and actively work with. If I can get things up and running like someone did for the NetBSD slides above with FreeBSD CURRENT and NetBSD CURRENT on my amd64 test machine (directions welcome :)..), I'll give the tests a shot again to see how divergent the performance results are between the two BSDs in this area. Thanks! -Garrett 1. http://people.freebsd.org/~kris/scaling/7.0%20Preview.pdf 2. http://www.youtube.com/watch?v=Mfb5_uG7BCA