![]() Soft updates dramatically improve the performance of UFS filesystems. The newfs(8) utility currently does not enable them by default. The FreeBSD installer enables soft updates by default. However custom built installations that do not specify the -U option to newfs(8) and the prebuilt UFS system images get filesystems without soft updates enabled. There are several testing sites that run benchmarks comparing the performance of Linux distributions versus BSD distributions. When they run filesystem comparison benchmarks they use newfs(8) to create the UFS filesystem. Because it does not have soft updates enabled it runs poorly versus the Linux ext4 filesystem. When I have suggested to them that they should enable soft updates on the UFS filesystem in their testing their response is that they expect the utility that creates the filesystem to use optimal defaults and that they cannot be expected to fiddle with various option settings. The purpose of this change is to give a filesystem created with newfs(8) reasonably optimal settings. For UFS2 this means enabling soft updates. For UFS1 which tends to be used on small systems with minimal memory and CPU speed, the lower memory footprint of running without soft updates is a more sensible default. This change adds a note in the section of the newfs(8) manual page that describes the -U option for enabling soft updates that they are enabled by default for UFS2 filesystems and that they can be disabled by using tunefs(8). Reviewed-by: Warner Losh, kib MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D45201 |
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.cirrus-ci | ||
.github | ||
bin | ||
cddl | ||
contrib | ||
crypto | ||
etc | ||
gnu | ||
include | ||
kerberos5 | ||
lib | ||
libexec | ||
release | ||
rescue | ||
sbin | ||
secure | ||
share | ||
stand | ||
sys | ||
targets | ||
tests | ||
tools | ||
usr.bin | ||
usr.sbin | ||
.arcconfig | ||
.arclint | ||
.cirrus.yml | ||
.clang-format | ||
.git-blame-ignore-revs | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
CONTRIBUTING.md | ||
COPYRIGHT | ||
LOCKS | ||
MAINTAINERS | ||
Makefile | ||
Makefile.inc1 | ||
Makefile.libcompat | ||
Makefile.sys.inc | ||
ObsoleteFiles.inc | ||
README.md | ||
RELNOTES | ||
UPDATING |
FreeBSD Source:
This is the top level of the FreeBSD source directory.
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), FreeBSD handbook on building userland, and Handbook for kernels for more information, including setting make(1) variables.
For information on the CPU architectures and platforms supported by FreeBSD, see the FreeBSD website's Platforms page.
For official FreeBSD bootable images, see the release page.
Source Roadmap:
Directory | Description |
---|---|
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 | Commands and libraries under the GNU General Public License (GPL) or Lesser General Public License (LGPL). Please see gnu/COPYING and gnu/COPYING.LIB 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 (see sys/README.md). |
targets | Support for experimental DIRDEPS_BUILD |
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 FreeBSD Handbook.