more weird bugs with mmap-ing via NFS
Oliver Fromme
olli at lurza.secnetix.de
Wed Mar 22 11:27:42 UTC 2006
Mikhail Teterin <mi+mx at aldan.algebra.com> wrote:
> (no softupdates). It was created with `-O1 -b 65536 -f 8192' as it is intended
> for large files and needs no ACLs (hence no UFS1).
Those values are very suboptimal. Whe creating a file system
for large files, you should rather decrease the inode density
(-i option). Using "-i 262144" should work fine, or even
"-i 1048576" (larger values don't make much sense, though).
Increasing block size and fragment size like that is not a
good idea. In fact, in earlier versions of FreeBSD there
were bugs which could lead to file system corruption when
64k block size was used. I don't know if those bugs have
been fixed -- maybe nobody knows, because nobody uses such
large block sizes, so they aren't extensively tested. ;-)
However, you could try setting block size and fragment size
to the same value, effectively disabling fragmentation (you
don't really need fragments when you have only large files).
For example, "-b 8192 -f 8192" should be OK.
Best regards
Oliver
--
Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing
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