Hello All,
On Wed, Sep 9, 2009 at 9:16 AM, Peter Teoh <[email protected]> wrote: > 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<[email protected]> > 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/
