2e310f6f72
Vast majority of uses the cache are just checking if there is an entry present on process exit (and evicting it if so). Both checking and eviction process are very expensive and put the lock protecting it high up on the profile during poudriere -j 104. Convert the linked list into a hash. This allows to almost always avoid taking the lock in the first place (and consequently almost removes it from the profile). Note only one lock is preserved as a split did not meaningfully impact contention. Should the cache be used for something it will still run into contention issues. The code needs a rewrite, but should someone want to tidy it up further the following can be done: 1) per-chain locks (or at least an array) 2) hashing by something else than just pid Sponsored by: The FreeBSD Foundation
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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.
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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.
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https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/current-stable.html