Gleb Smirnoff writes: > On Fri, May 25, 2007 at 10:57:54PM +0200, Andre Oppermann wrote: > A> Andrew Gallatin wrote: > A> > Andrew Gallatin [EMAIL PROTECTED] wrote: > A> >> gallatin 2007-05-25 19:38:32 UTC > A> >> > A> >> FreeBSD src repository > A> >> > A> >> Modified files: > A> >> sys/dev/mxge if_mxge.c Log: > A> >> - Use m_getcl() rather than m_getjcl() when we're allocating 2KB > A> >> clusters. This helps quite a bit on my low end machines (improves > A> >> performance by about 300Kpps when being blasted by a hardware > A> >> packet generator). > A> > BTW, thanks to bmilekic for reminding me of the packet zone. > A> > It would be nice if such a thing existed for the jumbo sized > A> > clusters :) > A> > A> Secondary zones are not perfectly integrated with UMA and there > A> are some nits that prevent doing just that for the moment. We're > A> working on it. It's not trivial though. I want to de-inline some > A> functions in mbuf.h to make backend changes transparent to consumers > A> of it. > > Just 1 penny: Andrews commit shows that packet zone shouldn't be deleted, > it really improves performance.
It is not clear that it always improves performance. I think it may have at least a little to do with the platform (athlon64 rather than xeon), and the fact that I allocate my receive buffers in the interrupt thread, rather than having a separate thread to allocate them. Both scottl and kmacy have reported substantial gains from allocating clusters well in advance (in a taskq for cxbe, not sure what scottl did for em) and allocating the pkthdr mbufs after the interrupt comes in. I did not notice an improvement when I tried allocating pkhdrs late (and I never tried a taskq/thread to allocate buffers). Again, it might be the platform. I'll try more experiments when I get access to Xeons again.. Speaking of mbufs, Bosko pointed out that in revision 1.156 of kern/uipc_mbuf.c, code was added which clears M_EXT information at mb_free_ext() time. He was concerned that doing this at free time might be cache unfriendly, and that this clearing used to be done at ctor time. Drew _______________________________________________ cvs-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/cvs-all To unsubscribe, send any mail to "[EMAIL PROTECTED]"
