On Wed, Sep 9, 2009 at 9:16 AM, Peter Teoh <htmldeveloper@xxxxxxxxx> wrote:
waiting for it....
Check this:
http://lkml.org/lkml/2007/10/4/50
http://lkml.org/lkml/2007/6/20/238
http://lkml.org/lkml/2006/9/8/4
blocksize and pagesize always have to match for optimum performance,
so max size for blocksize is pagesize.
not sure why u want to have large blocksize....check this:
http://lkml.indiana.edu/hypermail/linux/kernel/0510.2/0513.html
even if u want to update ONE byte....u have to lock the entire
blocksize....moreover...blocksize also affect application performance
(Oracle):
http://forums13.itrc.hp.com/service/forums/questionanswer.do?admit=109447627+1252466541647+28353475&threadId=1304351
so fundamentally, why the link between pagesize and blocksize?
well.....virtual memory operation is always physically contiguous at
the PAGESIZE level....so hardware wise there is no discontinuity when
u do a copy.
Thanks Peter for the links.
but then there exists something called scatter-gather I/O
APIs...allowing multiple discontinous range of physical I/O
operation.....no knowledge of that....perhaps someone can comment?
waiting for it....
On Fri, Sep 4, 2009 at 8:59 PM, Rishi Agrawal<rishi.b.agrawal@xxxxxxxxx> wrote:
--> Hello All,
>
> I found this paragraph while understanding file systems.
>
> "
> I assume that you are setting this up with ext3 and hence my answer ties to
> this. If your filesystem is different, you should say so.
>
> Note: *In ext3, an 8K block size on the fs is only possible if you use
> Itanium and other 8K architectures. If your architecture is x86, x86_64, it
> is not possible to have a block size greater than 4k*. If you try to make an
> ext3 fs you will fail with an error message similar to this:
>
> mkfs.ext3: 8192-byte blocks too big for system (max 4096)
>
> So,if your server architecture can take it, you can
> i)use parted post installation to make the partition and then type the
> following example (if your partition is called for instance /dev/sda2):
>
> mkfs -t ext3 -b 8192 /dev/sda2
> "
> link : http://osdir.com/ml/redhat-list/2009-06/msg00131.html
>
>
> I could not figure out the dependency between the file system block size and
> the architecture.
>
> Can somebody guide me in this ?
>
>
>
>
> --
> Regards,
> Rishi B. Agrawal
> http://www.linkedin.com/in/rishibagrawal
> http://code.google.com/p/fscops/
>
Regards,
Peter Teoh
--
Regards,
Rishi B. Agrawal
http://www.linkedin.com/in/rishibagrawal
http://code.google.com/p/fscops/
