Block Sizes

Karen Shaeffer shaeffer at
Thu Oct 31 13:11:26 EST 2002

On Thu, Oct 31, 2002 at 09:11:03AM -0800, Greg Lindahl wrote:
> On Thu, Oct 31, 2002 at 11:36:54AM -0500, Robert G. Brown wrote:
> > I think you'll want to create your partitions with -T largefile4, 4K
> > blocksize (the maximum, which I recall is also the kernel page size
> > which is probably WHY it is the maximum) which allocates one inode for
> > every 4 MB of disk.
> The question was about making I/O faster. What you suggest wastes less
> disk space on inodes, but won't speed up anything because ext2's usual
> blocksize is 4K. Larger blocks doesn't necessarily improve things, it
> really depends on whether their I/O is linear or random or whatever.

Using a RAID 5 disk array with n disks will result in an (n-1)X I/O
performance gain. With the price of disks today, it seems like a viable
option for folks who need the speed.

 Karen Shaeffer
 Neuralscape; Santa Cruz, Ca. 95060
 shaeffer at
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