restore(8) to UFS on USB key: terrible slow

[Hans Petter Selasky]

On Thursday 08 December 2011 10:19:43 Matthias Apitz wrote:
> El día Thursday, December 08, 2011 a las 10:10:36AM +0100, Hans Petter 
Selasky escribió:
> > > # fdisk -I da0
> > > # fdisk -B da0
> > > # bsdlabel -w da0s1 auto
> > > # bsdlabel -B da0s1
> > > # bsdlabel -e da0s1
> > > # newfs /dev/da0s1a
> > > # mount /dev/da0s1a /mnt
> > > 
> > > When I now bulk write a big file to the file system, the write
> > > performance is reasonable fast, even with blocks of 512 bytes,
> > > it gives 2 MByte / sec:
> > > 
> > > # dd if=usb.dmp of=/mnt/byte
> > > 10926520+0 records in
> > > 10926520+0 records out
> > > 5594378240 bytes transferred in 2538.942585 secs (2203428 bytes/sec)
> > 
> > Hello!
> > 
> > The default block size of dd is 512 bytes. Try setting bs=65536 :-)
> 
> Hello Hans,
> 
> I know (as I said) that dd(1) per default writes in blocks of 512 bytes;
> but this is not the problem; the problem is the poor performance of
> restore(8); the dd(1) was just to see if the USB key performs fast
> enough in general; please read my post again :-)

Hi,

The "restore" utility also has a -b option for blocksize. Did you try that?

--HPS