<link></link>
<atom:link href="index.rss" rel="self" type="application/rss+xml" />
+ <item>
+ <title>Debian boots quicker and quicker</title>
+ <link>Debian_boots_quicker_and_quicker.html</link>
+ <guid isPermaLink="true">Debian_boots_quicker_and_quicker.html</guid>
+ <pubDate>Wed, 24 Jun 2009 21:40:00 +0200</pubDate>
+ <description>
+<p>I spent Monday and tuesday this week in London with a lot of the
+people involved in the boot system on Debian and Ubuntu, to see if we
+could find more ways to speed up the boot system. This was an Ubuntu
+funded
+<a href="https://wiki.ubuntu.com/FoundationsTeam/BootPerformance/DebianUbuntuSprint">developer
+gathering</a>. It was quite productive. We also discussed the future
+of boot systems, and ways to handle the increasing number of boot
+issues introduced by the Linux kernel becoming more and more
+asynchronous and event base. The Ubuntu approach using udev and
+upstart might be a good way forward. Time will show.</p>
+
+<p>Anyway, there are a few ways at the moment to speed up the boot
+process in Debian. All of these should be applied to get a quick
+boot:</p>
+
+<ul>
+
+<li>Use dash as /bin/sh.</li>
+
+<li>Disable the init.d/hwclock*.sh scripts and make sure the hardware
+ clock is in UTC.</li>
+
+<li>Install and activate the insserv package to enable
+ <a href="http://wiki.debian.org/LSBInitScripts/DependencyBasedBoot">dependency
+ based boot sequencing</a>, and enable concurrent booting.</li>
+
+</ul>
+
+These points are based on the Google summer of code work done by
+<a href="http://initscripts-ng.alioth.debian.org/soc2006-bootsystem/">Carlos
+Villegas</a>.
+
+<p>Support for makefile-style concurrency during boot was uploaded to
+unstable yesterday. When we tested it, we were able to cut 6 seconds
+from the boot sequence. It depend on very correct dependency
+declaration in all init.d scripts, so I expect us to find edge cases
+where the dependences in some scripts are slightly wrong when we start
+using this.</p>
+
+<p>On our IRC channel for this effort, #pkg-sysvinit, a new idea was
+introduced by Raphael Geissert today, one that could affect the
+startup speed as well. Instead of starting some scripts concurrently
+from rcS.d/ and another set of scripts from rc2.d/, it would be
+possible to run a of them in the same process. A quick way to test
+this would be to enable insserv and run 'mv /etc/rc2.d/S* /etc/rcS.d/;
+insserv'. Will need to test if that work. :)</p>
+</description>
+ </item>
+
<item>
<title>Litt om valgfusk og problemet med elektronisk stemmegiving</title>
<link>Litt_om_valgfusk_og_problemet_med_elektronisk_stemmegiving.html</link>
</description>
</item>
- <item>
- <title>Two projects that have improved the quality of free software a lot</title>
- <link>Two_projects_that_have_improved_the_quality_of_free_software_a_lot.html</link>
- <guid isPermaLink="true">Two_projects_that_have_improved_the_quality_of_free_software_a_lot.html</guid>
- <pubDate>Sat, 2 May 2009 15:00:00 +0200</pubDate>
- <description>
-<p>There are two software projects that have had huge influence on the
-quality of free software, and I wanted to mention both in case someone
-do not yet know them.</p>
-
-<p>The first one is <a href="http://valgrind.org/">valgrind</a>, a
-tool to detect and expose errors in the memory handling of programs.
-It is easy to use, all one need to do is to run 'valgrind program',
-and it will report any problems on stdout. It is even better if the
-program include debug information. With debug information, it is able
-to report the source file name and line number where the problem
-occurs. It can report things like 'reading past memory block in file
-X line N, the memory block was allocated in file Y, line M', and
-'using uninitialised value in control logic'. This tool has made it
-trivial to investigate reproducible crash bugs in programs, and have
-reduced the number of this kind of bugs in free software a lot.
-
-<p>The second one is
-<a href="http://en.wikipedia.org/wiki/Coverity">Coverity</a> which is
-a source code checker. It is able to process the source of a program
-and find problems in the logic without running the program. It
-started out as the Stanford Checker and became well known when it was
-used to find bugs in the Linux kernel. It is now a commercial tool
-and the company behind it is running
-<a href="http://www.scan.coverity.com/">a community service</a> for the
-free software community, where a lot of free software projects get
-their source checked for free. Several thousand defects have been
-found and fixed so far. It can find errors like 'lock L taken in file
-X line N is never released if exiting in line M', or 'the code in file
-Y lines O to P can never be executed'. The projects included in the
-community service project have managed to get rid of a lot of
-reliability problems thanks to Coverity.</p>
-
-<p>I believe tools like this, that are able to automatically find
-errors in the source, are vital to improve the quality of software and
-make sure we can get rid of the crashing and failing software we are
-surrounded by today.</p>
-</description>
- </item>
-
</channel>
</rss>
projects / homepage.git / blobdiff