[linux-lvm] Why the dramatic increase in filesystem performance when usingxfs????

[David S.]

> 
> As the xfs performance comes back about twice the performance of ext3
> for this test I am of the opinion that xfs must be cheating somehow. It
> has always been my opinion that the IO bottleneck is the hardware and
> not the filesystem hence changing the filesystem but using the same
> hardware should not make a huge difference to performance (you still
> have to get the same amount of data out to disk at the end of the day)
> 
> I am struggling to comprehend how xfs can cheat, though, as it can't
> cache such a huge file as there is not enough memory. Is it perhaps
> cheating because the file is comprised entirely of zero's?
> 
> Can someone please enlighten me

Try mounting your ext3 file system with the "data=writeback" option.
See mount(8).

David S.

> 
> Thanks in advance
> 
> Gary Mansell
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