Date: Mon, 26 Nov 2007 14:12:26 -0800 From: Alfred Perlstein <alfred@freebsd.org> To: Robert Watson <rwatson@FreeBSD.org> Cc: Max Laier <max@love2party.net>, freebsd-current@freebsd.org, freebsd-net@freebsd.org Subject: Re: Switch pfil(9) to rmlocks Message-ID: <20071126221226.GJ71382@elvis.mu.org> In-Reply-To: <20071126203514.X65286@fledge.watson.org> References: <200711231232.04447.max@love2party.net> <20071126203514.X65286@fledge.watson.org>
next in thread | previous in thread | raw e-mail | index | archive | help
* Robert Watson <rwatson@FreeBSD.org> [071126 12:37] wrote: > > On Fri, 23 Nov 2007, Max Laier wrote: > > >attached is a diff to switch the pfil(9) subsystem to rmlocks, which are > >more suited for the task. I'd like some exposure before doing the switch, > >but I don't expect any fallout. This email is going through the patched > >pfil already - twice. > > FYI, since people are experimenting with rmlocks as a substitute for > rwlocks, I played with moving the global rwlock used to protect the name > space and linkage of UNIX domain sockets to be an rmlock. Kris didn't see > any measurable change in performance for his MySQL benchmarks, but I > figured I'd post the patches as they give a sense of what change impact > things like reader state management have on code. Attached below. I have > no current plans to commit these changes as they appear not to offer > benefit (either because the rwlock overhead was negigible compared to other > costs in the benchmark, or because the read/write blend was too scewed > towards writes -- I think probably the former rather than the latter). I would track the read/write lock mix to get an idea of what the ratio is. -Alfred
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20071126221226.GJ71382>