other note jonathan the box im using doesnt support the whole drive, but bsd's kernel doesnt once its loaded, i fear the rawdevices would bring me back to the unsupported drive in bios issue,
would raw dev use my bios's specs, or the bsd's specs, ill peek at the src, but if someone could comment that.. cheers ! neko --- On Mon, 8/25/08, Jonathan Gray <[EMAIL PROTECTED]> wrote: > From: Jonathan Gray <[EMAIL PROTECTED]> > Subject: Re: dd performance question > To: "Neko" <[EMAIL PROTECTED]> > Cc: misc@openbsd.org > Date: Monday, August 25, 2008, 11:24 PM > On Mon, Aug 25, 2008 at 06:58:30PM -0700, Neko wrote: > > Hi all, > > > > having a 250 GB drive on a PATA strip using lowest PIO > mode (without dma if possible), drive specs show a 8 MB > buffer , > > > > 2 cases are : on same pata strip, one on each strip, > > > > important to note that the booted drive is the > if's straight up to my slave. > > (yea i know ill have to run fsck afterwards since itll > think it still mounted) > > and having no user but su himself. > > > > i had ran mine at 4mb block space thinking ill use the > 16mb bus transfer > > divided at most in 4, per second, but i achieved that > in a minute instead. > > this is really poor performance, 3 days for 250gb > transfer at 4mb bs > > > > dd if=/dev/wd0c of=/dev/wd1c bs=4m > > This hits the buffer cache, use raw devices for anything > apart > from mounting, ie /dev/rwd0c
