From 04befc5e3cb597dca8f39a79e70b44a1ac5c019b Mon Sep 17 00:00:00 2001
From: Xi Ruoyao <xry111@xry111.site>
Date: Mon, 26 Aug 2024 02:49:01 +0800
Subject: [PATCH 1/3] aboutsbus: Add power profile info
---
chapter04/aboutsbus.xml | 27 ++++++++++++++++++++++++++-
1 file changed, 26 insertions(+), 1 deletion(-)
diff --git a/chapter04/aboutsbus.xml b/chapter04/aboutsbus.xml
index dccf59fe7..7139cb3a8 100644
--- a/chapter04/aboutsbus.xml
+++ b/chapter04/aboutsbus.xml
@@ -36,6 +36,32 @@
to give an estimate of how long it might take to install a package, but the
numbers can vary by as much as dozens of minutes in some cases.</para>
+ <para>Before measuring the build time of any package (no matter Binutils
+ pass 1 or a package of which the SBU is being measured), make sure a
+ system power profile suitable to make the system running with the
+ maximum performance (and the maximum power consumption) is selected. Or
+ the measured SBU value may be severly inaccurate because the system may be
+ operated differently building Binutils pass 1 and the other package.
+ Be aware that a significant inaccuracy can still show up even if the same
+ profile (except one maximizing the performance) is used for both packages:
+ the system may respond slower for <quote>saving the power</quote> building
+ Binutils pass 1, because the system load seems only about 25% of the load
+ building the other package (with <parameter>-j4</parameter>).</para>
+
+ <para>On most distros the power profile can be managed with either
+ <command>power-profiles-daemon</command> or <command>tuned</command>.
+ If the distro runs <command>power-profiles-daemon</command>, issue the
+ <command>powerprofilesctl set performance</command> command to select
+ the <literal>performance</literal> profile. If the distro runs
+ <command>tuned</command>, issue the <command>tuned-adm profile
+ throughput-performance</command> command to select the
+ <literal>throughput-performance</literal> profile.</para>
+
+ <para>Even if you are not measuring the SBU values, it's still better to
+ select the power profile for maximum performance before building LFS, as
+ doing so can (obviously) make the system faster to build LFS
+ packages.</para>
+
<note>
<para>When multiple processors are used in this way, the SBU units in the
book will vary even more than they normally would. In some cases, the make
@@ -47,7 +73,6 @@
<para>The times presented here are based upon using four cores (-j4). The
times in Chapter 8 also include the time to run the regression tests for
the package unless specified otherwise.</para>
-
</note>
</sect1>
From eae9237225b67996f68e473b5241c0d349f3d1f2 Mon Sep 17 00:00:00 2001
From: Bruce Dubbs <bdubbs@linuxfromscratch.org>
Date: Mon, 26 Aug 2024 17:59:31 -0500
Subject: [PATCH 2/3] Add more detail to the About SBUs page.
---
chapter04/aboutsbus.xml | 37 +++++++++++++++++++++++-------------
chapter05/binutils-pass1.xml | 2 +-
2 files changed, 25 insertions(+), 14 deletions(-)
diff --git a/chapter04/aboutsbus.xml b/chapter04/aboutsbus.xml
index 7139cb3a8..b65b30950 100644
--- a/chapter04/aboutsbus.xml
+++ b/chapter04/aboutsbus.xml
@@ -26,9 +26,9 @@
unit of time.</para>
<para>For example, consider a package whose compilation time is 4.5
- SBUs. This means that if your system took 10 minutes to compile and
+ SBUs. This means that if your system took 4 minutes to compile and
install the first pass of binutils, it will take
- <emphasis>approximately</emphasis> 45 minutes to build the example package.
+ <emphasis>approximately</emphasis> 18 minutes to build the example package.
Fortunately, most build times are shorter than one SBU.</para>
<para>SBUs are not entirely accurate because they depend on many
@@ -36,17 +36,26 @@
to give an estimate of how long it might take to install a package, but the
numbers can vary by as much as dozens of minutes in some cases.</para>
- <para>Before measuring the build time of any package (no matter Binutils
- pass 1 or a package of which the SBU is being measured), make sure a
- system power profile suitable to make the system running with the
- maximum performance (and the maximum power consumption) is selected. Or
- the measured SBU value may be severly inaccurate because the system may be
- operated differently building Binutils pass 1 and the other package.
+ <para>On some newer systems, the motherboard is capable of contolling
+ the system clock speed. This can be controlled with a command such as
+ <command>powerprofilesctl</command>. This is not available in LFS, but
+ may be available on the host system. After LFS is complete, it can be
+ added to a system with the procedures at the
+ <ulink url='&blfs-book;sysutils/power-profiles-daemon.html'>
+ BLFS power-profiles-daemon</ulink> page.
+
+ Before measuring the build time of any package it is advisable to use a
+ system power profile set for maximum performance (and maximum power
+ consumption).
+
+ Otherwise the measured SBU value may be inaccurate because the
+ system may react differently when building <xref linkend='ch-tools-binutils-pass1'/>
+ or other packages.
+
Be aware that a significant inaccuracy can still show up even if the same
- profile (except one maximizing the performance) is used for both packages:
- the system may respond slower for <quote>saving the power</quote> building
- Binutils pass 1, because the system load seems only about 25% of the load
- building the other package (with <parameter>-j4</parameter>).</para>
+ profile is used for both packages because the system may respond slower if
+ the system is idle when starting the build procedure. Setting the power
+ profile to "performance" will minimize this problem.</para>
<para>On most distros the power profile can be managed with either
<command>power-profiles-daemon</command> or <command>tuned</command>.
@@ -70,7 +79,9 @@
interleaved. If you run into a problem with a build step, revert to a
single processor build to properly analyze the error messages.</para>
- <para>The times presented here are based upon using four cores (-j4). The
+ <para>The times presented here for all packages
+ (except <xref linkend='ch-tools-binutils-pass1'/> which is based on one core)
+ are based upon using four cores (-j4). The
times in Chapter 8 also include the time to run the regression tests for
the package unless specified otherwise.</para>
</note>
diff --git a/chapter05/binutils-pass1.xml b/chapter05/binutils-pass1.xml
index 39365477d..f6b7f0f90 100644
--- a/chapter05/binutils-pass1.xml
+++ b/chapter05/binutils-pass1.xml
@@ -5,7 +5,7 @@
%general-entities;
]>
-<sect1 id="ch-tools-binutils-pass1" role="wrap">
+<sect1 id="ch-tools-binutils-pass1" role="wrap" xreflabel="binutils-pass1">
<?dbhtml filename="binutils-pass1.html"?>
<sect1info condition="script">
From 68c63ae3af63a55b0268c9c4802df3efff322562 Mon Sep 17 00:00:00 2001
From: Xi Ruoyao <xry111@xry111.site>
Date: Tue, 27 Aug 2024 12:31:04 +0800
Subject: [PATCH 3/3] Some About SBUs page reword
---
chapter04/aboutsbus.xml | 23 +++++++++--------------
1 file changed, 9 insertions(+), 14 deletions(-)
diff --git a/chapter04/aboutsbus.xml b/chapter04/aboutsbus.xml
index b65b30950..a442c20ab 100644
--- a/chapter04/aboutsbus.xml
+++ b/chapter04/aboutsbus.xml
@@ -39,7 +39,7 @@
<para>On some newer systems, the motherboard is capable of contolling
the system clock speed. This can be controlled with a command such as
<command>powerprofilesctl</command>. This is not available in LFS, but
- may be available on the host system. After LFS is complete, it can be
+ may be available on the host distro. After LFS is complete, it can be
added to a system with the procedures at the
<ulink url='&blfs-book;sysutils/power-profiles-daemon.html'>
BLFS power-profiles-daemon</ulink> page.
@@ -55,21 +55,16 @@
Be aware that a significant inaccuracy can still show up even if the same
profile is used for both packages because the system may respond slower if
the system is idle when starting the build procedure. Setting the power
- profile to "performance" will minimize this problem.</para>
+ profile to <quote>performance</quote> will minimize this problem. And
+ obviously doing so will also make the system build LFS faster.</para>
- <para>On most distros the power profile can be managed with either
- <command>power-profiles-daemon</command> or <command>tuned</command>.
- If the distro runs <command>power-profiles-daemon</command>, issue the
+ <para>If <command>powerprofilesctl</command> is available, issue the
<command>powerprofilesctl set performance</command> command to select
- the <literal>performance</literal> profile. If the distro runs
- <command>tuned</command>, issue the <command>tuned-adm profile
- throughput-performance</command> command to select the
- <literal>throughput-performance</literal> profile.</para>
-
- <para>Even if you are not measuring the SBU values, it's still better to
- select the power profile for maximum performance before building LFS, as
- doing so can (obviously) make the system faster to build LFS
- packages.</para>
+ the <literal>performance</literal> profile. Some distros provides the
+ <command>tuned-adm</command> command for managing the profiles instead of
+ <command>powerprofilesctl</command>, on these distros issue the
+ <command>tuned-adm profile throughput-performance</command> command to
+ select the <literal>throughput-performance</literal> profile.</para>
<note>
<para>When multiple processors are used in this way, the SBU units in the