Date: Sat, 3 Apr 2010 08:39:00 +0000 (UTC) From: Andriy Gapon <avg@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r206129 - head/sys/kern Message-ID: <201004030839.o338d0VV032828@svn.freebsd.org>
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Author: avg Date: Sat Apr 3 08:39:00 2010 New Revision: 206129 URL: http://svn.freebsd.org/changeset/base/206129 Log: vn_stat: take into account va_blocksize when setting st_blksize As currently st_blksize is always PAGE_SIZE, it is playing safe to not use any smaller value. For some cases this might not be optimal, but at least nothing should get broken. Generally I don't expect this commit to change much for the following reasons (in case of VREG, VDIR): - application I/O and physical I/O are sufficiently decoupled by filesystem code, buffer cache code, cluster and read-ahead logic - not all applications use st_blksize as a hint, some use f_iosize, some use fixed block sizes I expect writes to the middle of files on ZFS to benefit the most from this change. Silence from: fs@ MFC after: 2 weeks Modified: head/sys/kern/vfs_vnops.c Modified: head/sys/kern/vfs_vnops.c ============================================================================== --- head/sys/kern/vfs_vnops.c Sat Apr 3 08:25:04 2010 (r206128) +++ head/sys/kern/vfs_vnops.c Sat Apr 3 08:39:00 2010 (r206129) @@ -792,11 +792,10 @@ vn_stat(vp, sb, active_cred, file_cred, * "a filesystem-specific preferred I/O block size for this * object. In some filesystem types, this may vary from file * to file" - * Default to PAGE_SIZE after much discussion. - * XXX: min(PAGE_SIZE, vp->v_bufobj.bo_bsize) may be more correct. + * Use miminum/default of PAGE_SIZE (e.g. for VCHR). */ - sb->st_blksize = PAGE_SIZE; + sb->st_blksize = max(PAGE_SIZE, vap->va_blocksize); sb->st_flags = vap->va_flags; if (priv_check(td, PRIV_VFS_GENERATION))
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