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); _______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"