On Fri, 2009-05-29 at 10:09 -0400, Phil Schaffner wrote: > Alan Bartlett wrote: > ... > > Pedantically and ignoring the RAID aspect, just looking at the > > equations scientifically, I would say that only the first one is wrong > > as (64K / 4K) = 16, not 16K. It should be expressed as (64 / 4)K = > > 16K. > > > > The other two lines do read correctly but, in the spirit of > > conformity, I would suggest (3 * 16)K = 48K and (16 + 16)K = 32K, > > respectively. > > > > Perhaps the original author would care to comment and adjust where necessary? > > > > Alan. > > Direct link is http://wiki.centos.org/HowTos/Disk_Optimization to save > others from hunting through the top HowTos page. > > My pedantic sensibilities would render the equations as: > > (64K / 4K) = 16 > (3 * 16) = 48 > > The first would be consistent with the usage in item 9 in > > http://tldp.org/HOWTO/Software-RAID-0.4x-HOWTO-8.html > > and "man mke2fs": > > stride=stripe-size > Configure the filesystem for a RAID array with stripe-size > filesystem blocks per stripe. > > but the above points up another error on the Wiki page. There is no "-E > stripe-width" parameter to mkfs.ext3/mke2fs. I'd naively think it > should be "-E stride=48", but the conclusion is still that the original > author needs to respond, or failing that somebody else needs to fix the > errors. > > Phil Yes, that is a correct construct. It should look like: # mkfs.ext3 -E stride=8 /dev/... ...where stride = stripe/4K = 32K/4K = 8 in this raid10 example. Steve
