> Lance Larsh <llarsh@oracle.com> writes:
>>
>> I ran lots of iozone tests which illustrated a huge difference in write
>> throughput between reiser and ext2. Chris Mason sent me a patch which
>> improved the reiser case (removing an unnecessary commit), but it was
>> still noticeably slower than ext2. Therefore I would recommend that
>> at this time reiser should not be used for Oracle database files.
>
> When I read the 2.4.6 reiserfs code correctly reiserfs does not cause
> any transactions for reads/writes to allocated blocks; i.e. you're not extending
> the file, you're not filling holes and you're not updating atimes.
> My understanding is that this is normally true for Oracle, but probably
> not for iozone so it would be better if you benchmarked random writes
> to an already allocated file.
> The 2.4 page cache is more or less direct write through in this case.
>
In general, yes. But, atime updates trigger transactions, as
and O_SYNC/fsync writes (in 2.4.x reiserfs) always force a commit of
the current tranasction. The two patches I just posted should fix
that...
-chris
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/