blog/data/2010-05-06-concurrent-boot.txt

   1 Title: Parallellizing the boot in Debian Squeeze - ready for wider testing
   2 Tags: english, debian, bootsystem
   3 Date: 2010-05-06 23:25
   4
   5 <p>These days, the init.d script dependencies in Squeeze are quite
   6 complete, so complete that it is actually possible to run all the
   7 init.d scripts in parallell based on these dependencies.  If you want
   8 to test your Squeeze system, make sure
   9 <a href="http://wiki.debian.org/LSBInitScripts/DependencyBasedBoot">dependency
  10 based boot sequencing</a> is enabled, and add this line to
  11 /etc/default/rcS:</p>
  12
  13 <blockquote><pre>
  14 CONCURRENCY=makefile
  15 </pre></blockquote>
  16
  17 <p>That is it.  It will cause sysv-rc to use the startpar tool to run
  18 scripts in parallel using the dependency information stored in
  19 /etc/init.d/.depend.boot, /etc/init.d/.depend.start and
  20 /etc/init.d/.depend.stop to order the scripts.  Startpar is configured
  21 to try to start the kdm and gdm scripts as early as possible, and will
  22 start the facilities required by kdm or gdm as early as possible to
  23 make this happen.</p>
  24
  25 <p>Give it a try, and see if you like the result.  If some services
  26 fail to start properly, it is most likely because they have incomplete
  27 init.d script dependencies in their startup script (or some of their
  28 dependent scripts have incomplete dependencies).  Report bugs and get
  29 the package maintainers to fix it. :)</p>
  30
  31 <p>Running scripts in parallel could be the default in Debian when we
  32 manage to get the init.d script dependencies complete and correct.  I
  33 expect we will get there in Squeeze+1, if we get manage to test and
  34 fix the remaining issues.</p>
  35
  36 <p>If you report any problems with dependencies in init.d scripts to
  37 the BTS, please usertag the report to get it to show up at
  38 <a href="http://bugs.debian.org/cgi-bin/pkgreport.cgi?users=initscripts-ng-devel@lists.alioth.debian.org">the
  39 list of usertagged bugs related to this</a>.</p>