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John Baldwin 574862c8ba Enhance the sequential access heuristic used to perform readahead in the
NFS server and reuse it for writes as well to allow writes to the backing
store to be clustered.
- Use a prime number for the size of the heuristic table (1017 is not
  prime).
- Move the logic to locate a heuristic entry from the table and compute
  the sequential count out of VOP_READ() and into a separate routine.
- Use the logic from sequential_heuristic() in vfs_vnops.c to update the
  seqcount when a sequential access is performed rather than just
  increasing seqcount by 1.  This lets the clustering count ramp up
  faster.
- Allow for some reordering of RPCs and if it is detected leave the current
  seqcount as-is rather than dropping back to a seqcount of 1.  Also,
  when out of order access is encountered, cut seqcount in half rather than
  dropping it all the way back to 1 to further aid with reordering.
- Fix the new NFS server to properly update the next offset after a
  successful VOP_READ() so that the readahead actually works.

Some of these changes came from an earlier patch by Bjorn Gronwall that was
forwarded to me by bde@.

Discussed with:	bde, rmacklem, fs@
Submitted by:	Bjorn Gronwall (1, 4)
MFC after:	2 weeks
2011-12-01 18:46:28 +00:00
bin sh: Remove impossible evalskip check in 'for'. 2011-11-27 00:09:59 +00:00
cddl Merge new ZFS features from illumos: 2011-11-28 21:40:00 +00:00
contrib Reimport .texi and .texinfo necessary to build the info documentation. 2011-11-28 14:23:09 +00:00
crypto Add a -x option that causes ssh-agent(1) to exit when all clients have 2011-10-07 13:10:16 +00:00
etc Import libc++ / libcxxrt into base. Not build by default yet (use 2011-11-25 20:59:04 +00:00
games Add static keywords to variables and functions where possible in games/. 2011-11-05 07:18:53 +00:00
gnu upgrade gperf to the last GPLv2 version (3.0.3) 2011-11-28 12:29:16 +00:00
include Implement xlocale APIs from Darwin, mainly for use by libc++. This adds a 2011-11-20 14:45:42 +00:00
kerberos5 Link with -ledit instead of -lreadline. 2011-11-29 03:49:03 +00:00
lib Use INCSLINKS so that "make installincludes" installs links during buildworld. 2011-11-29 06:21:01 +00:00
libexec Fix fd leak. 2011-11-18 09:55:47 +00:00
release - Based on a report on sparc64@ move V245 to the list of known working 2011-11-27 16:50:13 +00:00
rescue -lreadline is not required anymore. 2011-11-29 03:27:09 +00:00
sbin If the -d flag is specified, ignore any new values specified and only 2011-12-01 15:01:23 +00:00
secure - add a missing "be" and "in" 2011-11-11 22:27:09 +00:00
share Add a man page describing the feed-forward clock kernel support, including how 2011-12-01 07:41:30 +00:00
sys Enhance the sequential access heuristic used to perform readahead in the 2011-12-01 18:46:28 +00:00
tools Add a simple test for pipe inode numbers reported by fstat(2). 2011-12-01 11:20:25 +00:00
usr.bin - Fix segmentation fault when running "+command" when run with -jX -n due 2011-11-30 18:07:38 +00:00
usr.sbin Sync xdialog_menu() implementation with sade. 2011-12-01 09:02:57 +00:00
COPYRIGHT Happy New Year 2011. 2010-12-31 18:07:16 +00:00
LOCKS Update LOCKS syntax. 2008-06-05 19:47:58 +00:00
MAINTAINERS Farewall, sysinstall! You served us well for many years, but 10.0 is one 2011-10-03 15:13:09 +00:00
Makefile Replace 'chflags' with 'file flags' in a comment, since 'chflags' 2011-11-20 20:05:47 +00:00
Makefile.inc1 - CTF knob is now implemented using common scheme: MK_CTF=yes/no is 2011-11-30 18:11:49 +00:00
Makefile.mips Retire TARGET_ABI. 2011-01-07 20:26:33 +00:00
ObsoleteFiles.inc Deorbit the broken amd(4) (see PR 124667), which was superseded by esp(4) 2011-11-25 19:29:21 +00:00
README Add the cddl/ directory. 2010-11-14 11:32:56 +00:00
UPDATING Add an entry for r227823. 2011-11-30 20:08:30 +00:00

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---------------
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cddl		Various commands and libraries under the Common Development
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