Squid and first-level subdirectories & second-level subdirectories on ext3/4

[Ralf Hildebrandt]

* Andreas Dilger <adilger at dilger.ca>:

> In ext3/4 the top-level inodes are spread around the filesystem, on the
> assumtion that something like /home or / is allocating trees of
> unrelated subdirectories at the top level, but that files within those
> subdirectories ARE related and should be allocated together.
> 
> Depending on how many files are in your cache, the 256 * {small files}
> is likely too big to fit into a single block group (32k inodes, 32k
> blocks) so you may want to consider marking the first level of
> subdirectories with the "TOPDIR" flag, that indicates the second-level
> (256) subdirs should also be spread around the disk.

How do I mark subdirectories with the "TOPDIR" flag?

-- 
Ralf Hildebrandt
  Geschäftsbereich IT | Abteilung Netzwerk
  Charité - Universitätsmedizin Berlin
  Campus Benjamin Franklin
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  ralf.hildebrandt at charite.de | http://www.charite.de