freebsd-nq/sys/nfsclient
Rick Macklem cf766161ff For software builds, the NFS client does many small
synchronous (with FILE_SYNC) writes because non-contiguous
byte ranges in the same buffer cache block are being
written. This patch adds a new mount option "noncontigwr"
which allows the non-contiguous byte ranges to be combined,
with the dirty byte range becoming the superset of the bytes
that are dirty, if the file has not been file locked.
This reduces the number of writes significantly for software
builds. The only case where this change might break existing
applications is where an application is writing
non-overlapping byte ranges within the same buffer cache block
of a file from multiple clients concurrently.
Since such an application would normally do file locking on
the file, avoiding the byte range merge for files that have
been file locked should be sufficient for most (maybe all?) cases.

Submitted by:	jhb (earlier version)
Reviewed by:	kib
MFC after:	3 weeks
2013-12-07 23:05:59 +00:00
..
nfs_bio.c - For kernel compiled only with KDTRACE_HOOKS and not any lock debugging 2013-11-25 07:38:45 +00:00
nfs_kdtrace.c
nfs_krpc.c - For kernel compiled only with KDTRACE_HOOKS and not any lock debugging 2013-11-25 07:38:45 +00:00
nfs_nfsiod.c When an NFS unmount occurs, once vflush() writes the last dirty 2013-04-18 23:20:16 +00:00
nfs_node.c r16312 is not any longer real since many years (likely since when VFS 2012-11-19 22:43:45 +00:00
nfs_subs.c - For kernel compiled only with KDTRACE_HOOKS and not any lock debugging 2013-11-25 07:38:45 +00:00
nfs_vfsops.c The r48589 promised to remove implicit inclusion of if_var.h soon. Prepare 2013-10-26 17:58:36 +00:00
nfs_vnops.c - For kernel compiled only with KDTRACE_HOOKS and not any lock debugging 2013-11-25 07:38:45 +00:00
nfs.h Fix a comment that got missed by r221973 which changed 2011-05-16 13:12:09 +00:00
nfsargs.h For software builds, the NFS client does many small 2013-12-07 23:05:59 +00:00
nfsm_subs.h - Use m_get2() instead of nfsm_reqhead(). 2013-03-12 12:23:47 +00:00
nfsmount.h Revert 195703 and 195821 as this special stop handling in NFS is now 2013-03-13 21:06:03 +00:00
nfsnode.h PR# 165923 reported intermittent write failures for dirty 2012-05-12 12:02:51 +00:00
nfsstats.h
nlminfo.h