resolved: cache stringified transaction key once per transaction

[thirdparty/systemd.git] / README

diff --git a/README b/README
index 777b34335ed7c9135e6c3fbf8f27d00a6505bc1f..bf67f8c03ed295d5b18bfb561fc86bcefc785c33 100644 (file)
--- a/README
+++ b/README
@@ -30,14 +30,14 @@ AUTHOR:
 
 LICENSE:
         LGPLv2.1+ for all code
 
 LICENSE:
         LGPLv2.1+ for all code

-        - except src/shared/MurmurHash2.c which is Public Domain
-        - except src/shared/siphash24.c which is CC0 Public Domain
+        - except src/basic/MurmurHash2.c which is Public Domain
+        - except src/basic/siphash24.c which is CC0 Public Domain

         - except src/journal/lookup3.c which is Public Domain
         - except src/udev/* which is (currently still) GPLv2, GPLv2+
 
 REQUIREMENTS:
         - except src/journal/lookup3.c which is Public Domain
         - except src/udev/* which is (currently still) GPLv2, GPLv2+
 
 REQUIREMENTS:

-        Linux kernel >= 3.7
-        Linux kernel >= 3.8 for Smack support
+        Linux kernel >= 3.11
+        Linux kernel >= 4.2 for unified cgroup hierarchy support

 
         Kernel Config Options:
           CONFIG_DEVTMPFS
 
         Kernel Config Options:
           CONFIG_DEVTMPFS


@@ -82,11 +82,11 @@ REQUIREMENTS:
           CONFIG_SECCOMP
           CONFIG_CHECKPOINT_RESTORE (for the kcmp() syscall)
 
           CONFIG_SECCOMP
           CONFIG_CHECKPOINT_RESTORE (for the kcmp() syscall)
 

-        Required for CPUShares in resource control unit settings
+        Required for CPUShares= in resource control unit settings

           CONFIG_CGROUP_SCHED
           CONFIG_FAIR_GROUP_SCHED
 
           CONFIG_CGROUP_SCHED
           CONFIG_FAIR_GROUP_SCHED
 

-        Required for CPUQuota in resource control unit settings
+        Required for CPUQuota= in resource control unit settings

           CONFIG_CFS_BANDWIDTH
 
         For systemd-bootchart, several proc debug interfaces are required:
           CONFIG_CFS_BANDWIDTH
 
         For systemd-bootchart, several proc debug interfaces are required:


@@ -97,6 +97,15 @@ REQUIREMENTS:
           CONFIG_EFIVAR_FS
           CONFIG_EFI_PARTITION
 
           CONFIG_EFIVAR_FS
           CONFIG_EFI_PARTITION
 

+        We recommend to turn off Real-Time group scheduling in the
+        kernel when using systemd. RT group scheduling effectively
+        makes RT scheduling unavailable for most userspace, since it
+        requires explicit assignment of RT budgets to each unit whose
+        processes making use of RT. As there's no sensible way to
+        assign these budgets automatically this cannot really be
+        fixed, and it's best to disable group scheduling hence.
+           CONFIG_RT_GROUP_SCHED=n
+

         Note that kernel auditing is broken when used with systemd's
         container code. When using systemd in conjunction with
         containers, please make sure to either turn off auditing at
         Note that kernel auditing is broken when used with systemd's
         container code. When using systemd in conjunction with
         containers, please make sure to either turn off auditing at


@@ -113,7 +122,7 @@ REQUIREMENTS:
 
         glibc >= 2.16
         libcap
 
         glibc >= 2.16
         libcap

-        libmount >= 2.20 (from util-linux)
+        libmount >= 2.27.1 (from util-linux)

         libseccomp >= 1.0.0 (optional)
         libblkid >= 2.24 (from util-linux) (optional)
         libkmod >= 15 (optional)
         libseccomp >= 1.0.0 (optional)
         libblkid >= 2.24 (from util-linux) (optional)
         libkmod >= 15 (optional)


@@ -135,13 +144,12 @@ REQUIREMENTS:
         During runtime, you need the following additional
         dependencies:
 
         During runtime, you need the following additional
         dependencies:
 

-        util-linux >= v2.26 required
+        util-linux >= v2.27.1 required

         dbus >= 1.4.0 (strictly speaking optional, but recommended)
         dracut (optional)
         PolicyKit (optional)
 
         dbus >= 1.4.0 (strictly speaking optional, but recommended)
         dracut (optional)
         PolicyKit (optional)
 

-        When building from git, you need the following additional
-        dependencies:
+        When building from git, the following tools are needed:

 
         pkg-config
         docbook-xsl
 
         pkg-config
         docbook-xsl


@@ -153,7 +161,10 @@ REQUIREMENTS:
         gperf
         python (optional)
         python-lxml (optional, but required to build the indices)
         gperf
         python (optional)
         python-lxml (optional, but required to build the indices)

-        sphinx (optional)
+
+        The build system is initialized with ./autogen.sh. A tar ball
+        can be created with:
+          git archive --format=tar --prefix=systemd-222/ v222 | xz > systemd-222.tar.xz

 
         When systemd-hostnamed is used, it is strongly recommended to
         install nss-myhostname to ensure that, in a world of
 
         When systemd-hostnamed is used, it is strongly recommended to
         install nss-myhostname to ensure that, in a world of


@@ -161,12 +172,6 @@ REQUIREMENTS:
         under all circumstances. In fact, systemd-hostnamed will warn
         if nss-myhostname is not installed.
 
         under all circumstances. In fact, systemd-hostnamed will warn
         if nss-myhostname is not installed.
 

-        To build HTML documentation for python-systemd using sphinx,
-        please first install systemd (using 'make install'), and then
-        invoke sphinx-build with 'make sphinx-<target>', with <target>
-        being 'html' or 'latexpdf'. If using DESTDIR for installation,
-        pass the same DESTDIR to 'make sphinx-html' invocation.
-

 USERS AND GROUPS:
         Default udev rules use the following standard system group
         names, which need to be resolvable by getgrnam() at any time,
 USERS AND GROUPS:
         Default udev rules use the following standard system group
         names, which need to be resolvable by getgrnam() at any time,


@@ -232,9 +237,9 @@ SYSV INIT.D SCRIPTS:
         needs to look like, and provide an implementation at the marked places.
 
 WARNINGS:
         needs to look like, and provide an implementation at the marked places.
 
 WARNINGS:

-        systemd will warn you during boot if /etc/mtab is not a
-        symlink to /proc/mounts. Please ensure that /etc/mtab is a
-        proper symlink.
+        systemd will freeze execution during boot if /etc/mtab exists
+        but is not a symlink to /proc/mounts. Please ensure that
+        /etc/mtab is a proper symlink.

 
         systemd will warn you during boot if /usr is on a different
         file system than /. While in systemd itself very little will
 
         systemd will warn you during boot if /usr is on a different
         file system than /. While in systemd itself very little will


@@ -258,7 +263,12 @@ WARNINGS:
         false positives will be triggered by code which violates
         some rules but is actually safe.
 
         false positives will be triggered by code which violates
         some rules but is actually safe.
 

+        Currently, systemd-timesyncd defaults to use the Google NTP
+        servers if not specified otherwise at configure time. You
+        really should not ship an OS or device with this default
+        setting. See DISTRO_PORTING for details.
+

 ENGINEERING AND CONSULTING SERVICES:
 ENGINEERING AND CONSULTING SERVICES:

-        ENDOCODE <https://endocode.com/> offers professional
-        engineering and consulting services for systemd. Please
-        contact Chris Kühl <chris@endocode.com> for more information.
+        Kinvolk (https://kinvolk.io) offers professional engineering
+        and consulting services for systemd. Please contact Chris Kühl
+        <chris@kinvolk.io> for more information.