Date: Sat, 20 Oct 2012 21:28:25 +0200 From: Ivan Voras <ivoras@freebsd.org> To: Rick Macklem <rmacklem@uoguelph.ca> Cc: "freebsd-hackers@freebsd.org Hackers" <freebsd-hackers@freebsd.org>, Nikolay Denev <ndenev@gmail.com> Subject: Re: NFS server bottlenecks Message-ID: <CAF-QHFXB=yfD2EPoQf4C8YyX=0BA0Awndg0QNsWO8_rq=StHhQ@mail.gmail.com> In-Reply-To: <191784842.2570110.1350737132305.JavaMail.root@erie.cs.uoguelph.ca> References: <CAF-QHFWY0drcrUpo7GGD1zQNSDWsEeB_LHAjEbUKrX2ovQHNxw@mail.gmail.com> <191784842.2570110.1350737132305.JavaMail.root@erie.cs.uoguelph.ca>
next in thread | previous in thread | raw e-mail | index | archive | help
On 20 October 2012 14:45, Rick Macklem <rmacklem@uoguelph.ca> wrote: > Ivan Voras wrote: >> I don't know how to interpret the rise in context switches; as this is >> kernel code, I'd expect no context switches. I hope someone else can >> explain. >> > Don't the mtx_lock() calls spin for a little while and then context > switch if another thread still has it locked? Yes, but are in-kernel context switches also counted? I was assuming they are light-weight enough not to count. > Hmm, I didn't look, but were there any tests using UDP mounts? > (I would have thought that your patch would mainly affect UDP mounts, > since that is when my version still has the single LRU queue/mutex. Another assumption - I thought UDP was the default. > As I think you know, my concern with your patch would be correctness > for UDP, not performance.) Yes.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAF-QHFXB=yfD2EPoQf4C8YyX=0BA0Awndg0QNsWO8_rq=StHhQ>