В Sat, 23 Mar 2013 23:47:52 +0100 Lennart Poettering <lenn...@poettering.net> пишет:
> On Sat, 23.03.13 23:42, Tom Gundersen (t...@jklm.no) wrote: > > > > > On Sat, Mar 23, 2013 at 2:16 AM, Lennart Poettering > > <lenn...@poettering.net> wrote: > > > Then, I generally believe better than trying to be smart when reading > > > things we should much rather try to place things properly on disk. We > > > already defrag things based on the read order for btrfs, we should do > > > the same for ext4. The API for that unfortunately awful, but e4rat has > > > shown that this does work. Basically, this is what you do: > > > > Isn't the problem that reads by blkid and friends are not being caught > > by readahead-collect, and hence end up blocking until readahead-replay > > has finished? In that case reordering won't help (I think). > > Hmm, if root file system is mounted the file system's superblock should > be cached in memory, I'd expect, so blkid shouldn't have to block... > Filesystem caches superblock copy, not physical device block(s) where it is located. After it is copied, blocks are not more in use. _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
