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Kirk McKusick ad8ac923fa These changes appear to give us benefits with both small (32MB) and
large (1G) memory machine configurations.  I was able to run 'dbench 32'
on a 32MB system without bring the machine to a grinding halt.

    * buffer cache hash table now dynamically allocated.  This will
      have no effect on memory consumption for smaller systems and
      will help scale the buffer cache for larger systems.

    * minor enhancement to pmap_clearbit().  I noticed that
      all the calls to it used constant arguments.  Making
      it an inline allows the constants to propogate to
      deeper inlines and should produce better code.

    * removal of inherent vfs_ioopt support through the emplacement
      of appropriate #ifdef's, with John's permission.  If we do not
      find a use for it by the end of the year we will remove it entirely.

    * removal of getnewbufloops* counters & sysctl's - no longer
      necessary for debugging, getnewbuf() is now optimal.

    * buffer hash table functions removed from sys/buf.h and localized
      to vfs_bio.c

    * VFS_BIO_NEED_DIRTYFLUSH flag and support code added
      ( bwillwrite() ), allowing processes to block when too many dirty
      buffers are present in the system.

    * removal of a softdep test in bdwrite() that is no longer necessary
      now that bdwrite() no longer attempts to flush dirty buffers.

    * slight optimization added to bqrelse() - there is no reason
      to test for available buffer space on B_DELWRI buffers.

    * addition of reverse-scanning code to vfs_bio_awrite().
      vfs_bio_awrite() will attempt to locate clusterable areas
      in both the forward and reverse direction relative to the
      offset of the buffer passed to it.  This will probably not
      make much of a difference now, but I believe we will start
      to rely on it heavily in the future if we decide to shift
      some of the burden of the clustering closer to the actual
      I/O initiation.

    * Removal of the newbufcnt and lastnewbuf counters that Kirk
      added.  They do not fix any race conditions that haven't already
      been fixed by the gbincore() test done after the only call
      to getnewbuf().  getnewbuf() is a static, so there is no chance
      of it being misused by other modules.  ( Unless Kirk can think
      of a specific thing that this code fixes.  I went through it
      very carefully and didn't see anything ).

    * removal of VOP_ISLOCKED() check in flushbufqueues().  I do not
      think this check is necessary, the buffer should flush properly
      whether the vnode is locked or not. ( yes? ).

    * removal of extra arguments passed to getnewbuf() that are not
      necessary.

    * missed cluster_wbuild() that had to be a cluster_wbuild_wb() in
      vfs_cluster.c

    * vn_write() now calls bwillwrite() *PRIOR* to locking the vnode,
      which should greatly aid flushing operations in heavy load
      situations - both the pageout and update daemons will be able
      to operate more efficiently.

    * removal of b_usecount.  We may add it back in later but for now
      it is useless.  Prior implementations of the buffer cache never
      had enough buffers for it to be useful, and current implementations
      which make more buffers available might not benefit relative to
      the amount of sophistication required to implement a b_usecount.
      Straight LRU should work just as well, especially when most things
      are VMIO backed.  I expect that (even though John will not like
      this assumption) directories will become VMIO backed some point soon.

Submitted by:	Matthew Dillon <dillon@backplane.com>
Reviewed by:	Kirk McKusick <mckusick@mckusick.com>
1999-07-08 06:06:00 +00:00
bin
contrib
crypto
etc Do away with ${network_interfaces} in rc.conf. Just use ifconfig -l to 1999-07-07 12:49:47 +00:00
games
gnu Respect the NOFSCHG variable. Add an $Id$ while I'm here, for whatever 1999-07-05 02:46:20 +00:00
include
kerberos5
kerberosIV
lib Back out previous commit after discussing it with Dmitrij Tejblum. 1999-07-07 21:01:20 +00:00
libexec
release invoke fvwm properly 1999-07-07 09:47:41 +00:00
sbin Remove reference to the obsoleted COMCONSOLE option. 1999-07-06 11:45:27 +00:00
secure
share - Fix Belgian keyboard map (be.iso.kbd). 1999-07-07 13:20:12 +00:00
sys These changes appear to give us benefits with both small (32MB) and 1999-07-08 06:06:00 +00:00
tools
usr.bin Break lines to be < 80 chars. This has been done only to that file in 1999-07-07 06:44:53 +00:00
usr.sbin Do not list a null string in a dialog box. 1999-07-07 13:20:38 +00:00
COPYRIGHT
Makefile
Makefile.inc0
Makefile.inc1 Per requests from the community, commit rudimentary cross compilation 1999-07-07 04:46:46 +00:00
Makefile.upgrade
README
UPDATING Spelling nits 1999-07-07 04:28:48 +00:00

This is the top level of the FreeBSD source directory.  This file
was last revised on: $Id: README,v 1.13 1998/09/13 09:38:34 markm Exp $

For copyright information, please see the file COPYRIGHT in this
directory (additional copyright information also exists for some
sources in this tree - please see the specific source directories for
more information).

The Makefile in this directory supports a number of targets for
building components (or all) of the FreeBSD source tree, the most
commonly used one being ``world'', which rebuilds and installs
everything in the FreeBSD system from the source tree except the
kernel and the contents of /etc.  Please see the top of the Makefile
in this directory for more information on the standard build targets
and compile-time flags.

Building a kernel with config(8) is a somewhat more involved process,
documentation for which can be found at:
   http://www.freebsd.org/handbook/kernelconfig.html
And in the config(8) man page.

The sample kernel configuration files reside in the sys/i386/conf
sub-directory (assuming that you've installed the kernel sources), the
file named GENERIC being the one used to build your initial installation
kernel.  The file LINT contains entries for all possible devices, not
just those commonly used, and is meant more as a general reference
than an actual kernel configuration file (a kernel built from it
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Source Roadmap:
---------------
bin		System/User commands.

contrib		Packages contributed by 3rd parties.

crypto		Export controlled stuff (see crypto/README).

etc		Template files for /etc

games		Amusements.

gnu		Various commands and libraries under the GNU Public License.
		Please see gnu/COPYING* for more information.

include		System include files.

kerberosIV	Kerberos package.

lib		System libraries.

libexec		System daemons.

release		Release building Makefile & associated tools.

sbin		System commands.

secure		DES and DES-related utilities - NOT FOR EXPORT!

share		Shared resources.

sys		Kernel sources.

tools		Utilities for regression testing and miscellaneous tasks.

usr.bin		User commands.

usr.sbin	System administration commands.


For information on synchronizing your source tree with one or more of
the FreeBSD Project's development branches, please see:

  http://www.freebsd.org/handbook/synching.html