Should exclude very large files

[Bernhard Kappler]

Binary package hint: ureadahead

I've setup 3 virtual systems (KVM) which are automatically started at system boot. Since several weeks I had issues with the virtual systems frequently panicking at boot time and a high system load on the host system (load of 6 to 22).
Today I realized that this is caused by ureadahead attempting to "cache" the image files used by my virtual systems.

I've disabled /etc/init/ureadahead-other.conf such that ureadahead will no longer attempt to cache the image files. Since then my virtual systems are booting without issues and the system load during boot up remains below 3.

As a fix to ureadahead, I suggest to either ignore big files (the image files have 6-10GB) or to document how-to exclude certain files or mount points from being processed by ureadahead.

[Scott James Remnant (Canonical) (canonical-scott)]

Very large files is probably the right cut-off

[Lars Ola Liavåg (l-liavag)]

Coming from bug #491956, I can confirm having the same problem. I'm running a 32-bit Karmic on a Pentium D-based desktop but have the same on an older P4 system. The longer boot times have been there since sreadahead was replaced by ureadahead shortly after karmic was released. Removing the pack file to force a reprofile has repeatedly proved that without ureadahead, the boot is 5-10 seconds faster. I've attached the output of sudo ureadahead --dump pack --sort=size.

[Lars Ola Liavåg (l-liavag)]

Migrated to Lucid recently and I now seem to gain up to five seconds when ureadahead is used compared to when it's reprofiling.