Re: [PATCH] Add ext3 data=guarded mode

[Theodore Tso]

On Fri, Apr 17, 2009 at 11:39:06PM +0530, Amit Shah wrote:
> # 4GiB file, kernel 9f76208c33984ab777eace5d07a4e36e88703e02 + ext3-guarded
> 
> filesystem	posix-fallocate	mmap	chunk-4096	chunk-8192
> ext3-guarded	85		97	459		90
> ext3-writeback 86		95	140		94
> ext3-ordered	86		96	277		95
> 
> Running the test in single user mode, I get the following results:
> 
> # 4GiB file, kernel 9f76208c33984ab777eace5d07a4e36e88703e02 + ext3-guarded
> 
> filesystem	posix-fallocate	mmap	chunk-4096	chunk-8192
> ext3-guarded	84		86	163		91
> ext3-writeback 84		88	217		91
> ext3-ordered	84		86	226		91


The difference between guarded and writeback in chunk-4096 looking at
your desktop timings and your single user times is.... surprising. 

In particular, the fact that the guarded time is 3 times longer than
ext3-writeback when the desktop is running, and 20% faster in single
user mode.  Are these results reproducible?  And do you have any
thoughts as to what might be causing them?

					- Ted
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/