freebsd with flexible iflib nic queues
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Alexander Motin 3bae917061 Minimize aggsum_compare(&arc_size, arc_c) calls.
For busy ARC situation when arc_size close to arc_c is desired.  But
then it is quite likely that aggsum_compare(&arc_size, arc_c) will need
to flush per-CPU buckets to find exact comparison result.  Doing that
often in a hot path penalizes whole idea of aggsum usage there, since it
replaces few simple atomic additions with dozens of lock acquisitions.

Replacing aggsum_compare() with aggsum_upper_bound() in code increasing
arc_p when ARC is growing (arc_size < arc_c) according to PMC profiles
allows to save ~5% of CPU time in aggsum code during sequential write
to 12 ZVOLs with 16KB block size on large dual-socket system.

I suppose there some minor arc_p behavior change due to lower precision
of the new code, but I don't think it is a big deal, since it should
affect only very small window in time (aggsum buckets are flushed every
second) and in ARC size (buckets are limited to 10 average ARC blocks
per CPU).

MFC after:	2 weeks
Sponsored by:	iXsystems, Inc.
2019-06-14 20:04:28 +00:00
bin Some devices take undesired actions when RTS and DTR are 2019-06-12 18:07:04 +00:00
cddl DTrace: add a top level makefile to the new test suit 2019-06-09 22:45:07 +00:00
contrib Upgrade our copies of clang, llvm, lld, lldb, compiler-rt, libc++, 2019-06-12 21:10:37 +00:00
crypto Complete LOCAL_PEERCRED support. Cache pid of the remote process in the 2019-05-30 14:24:26 +00:00
etc Upgrade our copies of clang, llvm, lld, lldb, compiler-rt, libc++, 2019-06-12 21:10:37 +00:00
gnu
include Import OpenSSL 1.1.1c. 2019-05-28 20:08:17 +00:00
kerberos5
lib Upgrade our copies of clang, llvm, lld, lldb, compiler-rt, libc++, 2019-06-12 21:10:37 +00:00
libexec /etc/rc.d/local: Fix typo in description 2019-06-10 13:34:18 +00:00
release Revert r348438. 2019-05-31 18:40:19 +00:00
rescue
sbin Clarify that the -r and -R options can be used only to create level 0 dumps. 2019-06-14 06:10:15 +00:00
secure Merge OpenSSL 1.1.1c. 2019-05-28 21:54:12 +00:00
share Some devices take undesired actions when RTS and DTR are 2019-06-12 18:07:04 +00:00
stand Fix gcc build by removing redeclaration 2019-06-13 03:48:36 +00:00
sys Minimize aggsum_compare(&arc_size, arc_c) calls. 2019-06-14 20:04:28 +00:00
targets
tests Add test cases for epair 2019-06-13 05:05:58 +00:00
tools Upgrade our copies of clang, llvm, lld, lldb, compiler-rt, libc++, 2019-06-12 21:10:37 +00:00
usr.bin MFV r348971,r348977: 2019-06-12 13:34:12 +00:00
usr.sbin bhyve: move common code to net_utils.c 2019-06-13 17:39:32 +00:00
.arcconfig
.arclint
.cirrus.yml
.clang-format Add a basic clang-format configuration file 2019-06-07 15:23:52 +00:00
.gitattributes Add a basic clang-format configuration file 2019-06-07 15:23:52 +00:00
.gitignore Update vendor/libarchive/dist to git 614110e76d9dbb9ed3e159a71cbd75fa3b23efe3 2019-06-11 23:16:13 +00:00
COPYRIGHT
LOCKS
MAINTAINERS
Makefile
Makefile.inc1 Makefile.inc1: clean up stale dependency hacks 2019-06-04 12:56:20 +00:00
Makefile.libcompat
Makefile.sys.inc
ObsoleteFiles.inc Upgrade our copies of clang, llvm, lld, lldb, compiler-rt, libc++, 2019-06-12 21:10:37 +00:00
README Import OpenSSL 1.1.1c. 2019-05-28 20:08:17 +00:00
README.md Update vendor/libarchive/dist to git 614110e76d9dbb9ed3e159a71cbd75fa3b23efe3 2019-06-11 23:16:13 +00:00
UPDATING Upgrade our copies of clang, llvm, lld, lldb, compiler-rt, libc++, 2019-06-12 21:10:37 +00:00

FreeBSD Source:

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

FreeBSD is an operating system used to power modern servers, desktops, and embedded platforms. A large community has continually developed it for more than thirty years. Its advanced networking, security, and storage features have made FreeBSD the platform of choice for many of the busiest web sites and most pervasive embedded networking and storage devices.

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), config(8), https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html, and https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html for more information, including setting make(1) variables.

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.

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.

stand		Boot loader sources.

sys		Kernel sources.

sys/<arch>/conf Kernel configuration files. GENERIC is the configuration
		used in release builds. NOTES contains documentation of
		all possible entries.

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:

https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/current-stable.html