Date: Fri, 2 Mar 2007 15:48:34 +0100 From: Divacky Roman <xdivac02@stud.fit.vutbr.cz> To: Wojciech Puchar <wojtek@tensor.3miasto.net> Cc: freebsd-performance@freebsd.org, "O. Hartmann" <ohartman@zedat.fu-berlin.de>, freebsd-questions@freebsd.org Subject: Re: (S)ATA performance in FBSD 6.2/7.0 Message-ID: <20070302144833.GA87211@stud.fit.vutbr.cz> In-Reply-To: <20070302104219.B5845@chylonia.3miasto.net> References: <45E7F09B.7070005@zedat.fu-berlin.de> <20070302104219.B5845@chylonia.3miasto.net>
next in thread | previous in thread | raw e-mail | index | archive | help
On Fri, Mar 02, 2007 at 10:43:34AM +0100, Wojciech Puchar wrote: > >another while the box didn't do anything else than copying. I watched the > >copy process via 'systat -vmstat 1' and realized, that the value of 'KB/t' > >never go byond 128 (128kb buffer limit?). But more frustrating, I never got > > what's wrong? FreeBSD uses 128k limit by default. > > edit /usr/src/sys/sys/param.h > > and change > > #define MAXPHYS (128 * 1024) /* max raw I/O transfer size */ > > > to say > > #define MAXPHYS (1024 * 1024) /* max raw I/O transfer size */ did anyone measure impact on various benchmark of this change? is 128k the optimal size for "nowadays computers" ? if we can squeeze more performance out of a typical box by just raising one define it would be great... roman
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20070302144833.GA87211>