freebsd kernel with SKQ
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Alexander Motin 869fd29a7b Rewrite physio() to not allocate pbufs for unmapped I/O.
pbufs is a limited resource, and their allocator is not SMP-scalable.
So instead of always allocating pbuf to immediately convert it to bio,
allocate bio just here.  If buffer needs kernel mapping, then pbuf is
still allocated, but used only as a source of KVA and storage for a list
of held pages.

On 40-core system doing many 512-byte reads from user level to array of
raw SSDs this change removes huge lock congestion inside pbuf allocator.
It improves peak performance from ~300K to ~1.2M IOPS.  On my previous
24-core system this problem also existed, but was less serious.

Reviewed by:	kib
MFC after:	2 weeks
2015-04-21 10:55:53 +00:00
bin ed(1): Fix [-Werror=logical-not-parentheses] 2015-04-20 02:07:57 +00:00
cddl Add manual pages for the io, ip, proc, sched, tcp and udp DTrace providers. 2015-04-18 21:00:36 +00:00
contrib Merge bmake-20150418 2015-04-21 04:40:38 +00:00
crypto Use proper CHAN_TCP_PACKET_DEFAULT for agent forwarding when HPN disabled. 2015-04-02 18:43:25 +00:00
etc Remove some oldnfs remnants. 2015-04-18 16:08:06 +00:00
games fortune/tools/do_uniq.py 2015-04-02 22:42:23 +00:00
gnu Exclude the floating-point functions from libgcc_s on arm64, they are 2015-04-02 17:06:15 +00:00
include Move ALTQ from contrib to net/altq. The ALTQ code is for many years 2015-04-16 20:22:40 +00:00
kerberos5 Add a ${CP} alias for copying files in the build. 2015-01-16 21:39:08 +00:00
lib Fix improbable memory leak in _citrus_prop_read_str(). 2015-04-20 22:09:50 +00:00
libexec Use the correct value to get the offset of the objects tls data. 2015-04-15 14:20:12 +00:00
release Simplify variable expansion in attempt to fix the vm-image build. 2015-04-21 02:49:44 +00:00
rescue Significant upgrades to sa(4) and mt(1). 2015-02-23 21:59:30 +00:00
sbin dmesg: accommodate message buffer growth between the sysctl calls 2015-04-20 20:07:39 +00:00
secure Add the openssl header for arm64. As it is based on MACHINE_CPUARCH it 2015-03-24 14:16:14 +00:00
share Minor mdoc fixes. 2015-04-20 21:19:26 +00:00
sys Rewrite physio() to not allocate pbufs for unmapped I/O. 2015-04-21 10:55:53 +00:00
tests Add some new modes to OpenCrypto. These modes are AES-ICM (can be used 2014-12-12 19:56:36 +00:00
tools Tweak BSS symbol handling from r281811 to not consider them unresolved 2015-04-21 05:41:56 +00:00
usr.bin Merge bmake-20150418 2015-04-21 04:40:38 +00:00
usr.sbin Add hint about "volmode=dev" to ctl.conf(5). 2015-04-21 09:11:28 +00:00
.arcconfig phabricator related changes: 2015-04-20 20:33:22 +00:00
.arclint phabricator related changes: 2015-04-20 20:33:22 +00:00
COPYRIGHT Bump copyright year. 2014-12-31 10:00:43 +00:00
LOCKS
MAINTAINERS Remove cokane@ from MAINTAINERS for 3dfx(4)/tdfx(4) because their email 2014-11-25 05:25:12 +00:00
Makefile Add arm64 to universe if binutils is available. 2015-04-16 22:35:19 +00:00
Makefile.inc1 Serialize all of _kerberos5_bootstrap_tools to avoid build failures involving 2015-04-21 10:17:25 +00:00
ObsoleteFiles.inc Remove some oldnfs remnants. 2015-04-18 16:08:06 +00:00
README README: changes and fixups 2015-04-19 07:16:44 +00:00
UPDATING Make it harder to specify invalid LIBADD by causing values without 2015-04-16 15:34:22 +00:00

This is the top level of the FreeBSD source directory.  This file
was last revised on:
$FreeBSD$

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.  See build(7)
and http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html
for more information, including setting make(1) variables.

The `buildkernel` and `installkernel` targets build and install
the kernel and the modules (see below).  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 is a somewhat more involved process.  See build(7), config(8),
and http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html
for more information.

Note: If you want to build and install the kernel with the
`buildkernel` and `installkernel` targets, you might need to build
world before.  More information is available in the handbook.

The kernel configuration files reside in the sys/<arch>/conf
sub-directory.  GENERIC is the default configuration used in release builds.
NOTES contains entries and documentation for all possible
devices, not just those commonly used.


Source Roadmap:
---------------

bin		System/user commands.

cddl		Various commands and libraries under the Common Development
		and Distribution License.

contrib		Packages contributed by 3rd parties.

crypto		Cryptography 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.

kerberos5	Kerberos5 (Heimdal) package.

lib		System libraries.

libexec		System daemons.

release		Release building Makefile & associated tools.

rescue		Build system for statically linked /rescue utilities.

sbin		System commands.

secure		Cryptographic libraries and commands.

share		Shared resources.

sys		Kernel sources.

tests		Regression tests which can be run by Kyua.  See tests/README
		for additional information.

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/doc/en_US.ISO8859-1/books/handbook/synching.html