Parallellized boot is now the default in Debian/unstable
14th May 2010
Since this evening, parallel booting is the default in Debian/unstable for machines using dependency based boot sequencing. Apparently the testing of concurrent booting has been wider than expected, if I am to believe the input on debian-devel@, and I concluded a few days ago to move forward with the feature this weekend, to give us some time to detect any remaining problems before Squeeze is frozen. If serious problems are detected, it is simple to change the default back to sequential boot. The upload of the new sysvinit package also activate a new upstream version.
More information about dependency based boot sequencing is available from the Debian wiki. It is currently possible to disable parallel booting when one run into problems caused by it, by adding this line to /etc/default/rcS:CONCURRENCY=none
If you report any problems with dependencies in init.d scripts to the BTS, please usertag the report to get it to show up at the list of usertagged bugs related to this.