Because you can't start at 0 because the partition table is there, so it gets rounded to somewhere that is not aligned.
Sent from my android device. -----Original Message----- From: Erwan Velu <[email protected]> To: "Bendtsen, Jon" <[email protected]> Cc: "<[email protected]>" <[email protected]> Sent: Thu, 08 Aug 2013 10:50 AM Subject: Re: Question about optimal io size In fact, with percent it works. My question was more why does starting from 0 isn't considered as valid for big optimal_io_size. When my disk does have an optimal_io_size=256K it works, with a 1MB optimal_io_size it fails. 2013/8/8 Bendtsen, Jon <[email protected]> > On 08/08/2013, at 15.10, Erwan Velu <[email protected]> > wrote: > > > Hi folks, > > > > When doing a "parted -a optimal /dev/sdb mkpart primary 0 100%", parted > tells me that the partition will not be optimal. > > > Try "parted -a optimal /dev/sdb unit % mkpart primary 0 100%" > > > > JonB >
