Date: Mon, 9 Aug 2010 22:22:46 +0000 (UTC) From: Ivan Voras <ivoras@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r211123 - head/sys/kern Message-ID: <201008092222.o79MMkpp023928@svn.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: ivoras Date: Mon Aug 9 22:22:46 2010 New Revision: 211123 URL: http://svn.freebsd.org/changeset/base/211123 Log: Elaborate on how hirunningspace was chosen. Modified: head/sys/kern/vfs_bio.c Modified: head/sys/kern/vfs_bio.c ============================================================================== --- head/sys/kern/vfs_bio.c Mon Aug 9 22:22:06 2010 (r211122) +++ head/sys/kern/vfs_bio.c Mon Aug 9 22:22:46 2010 (r211123) @@ -622,8 +622,11 @@ bufinit(void) /* * Note: The 16 MB upper limit for hirunningspace was chosen - * arbitrarily and may need further tuning. The lower 1 MB - * limit is the historical upper limit for hirunningspace. + * arbitrarily and may need further tuning. It corresponds to + * 128 outstanding write IO requests (if IO size is 128 KiB), + * which fits with many RAID controllers' tagged queing limits. + * The lower 1 MB limit is the historical upper limit for + * hirunningspace. */ hirunningspace = lmax(lmin(roundup(hibufspace / 64, MAXBSIZE), 16 * 1024 * 1024), 1024 * 1024);
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201008092222.o79MMkpp023928>