* Morten Hustveit: > > This patch ensures that the package iterator used by > > ensure_allinstfiles_available returns the packages sorted by their .list > > file's physical location on the harddisk, greatly reducing drive head > > movements.
On Sat, Sep 05, 2009 at 09:03:03AM +0000, Florian Weimer wrote: > Have you tried using readdir() and sorting by the d_ino field? That > should be even faster for ext3 because you hit the inode in disk > order. I haven't tried this, because it would require much more changes to the dpkg code. The "FIBMAP every .list file" step takes less than one second when operating from a cold disk cache, probably because inodes aren't as scattered as file contents. I did try to use posix_fadvise + POSIX_FADV_WILLNEED on the next file each time iterpkgnext() was called, so that the kernel would be reading file N+1 while dpkg was processing file N. This cut approximately 0.5 seconds from my 8.0 second execution time; not a very interesting improvement in my opinion. -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
