restore of file system into USB key terrible slow

[Matthias Apitz]

Hello,

I'm trying to restore a DUMP into an USB key; the DUMP was extracted
from another USB key which I just want to colne this way;

the USB key type is:

Aug  5 10:53:34 rebelion kernel: da0 at umass-sim0 bus 0 target 0 lun 0
Aug  5 10:53:34 rebelion kernel: da0: < Cn Memory 1100> Removable Direct Access SCSI-0 device 
Aug  5 10:53:34 rebelion kernel: da0: 40.000MB/s transfers
Aug  5 10:53:34 rebelion kernel: da0: 3871MB (7928832 512 byte sectors: 255H 63S/T 493C)

and I've created a partition (only one covering the full ~4 GByte) and a
file system as:

# newfs -m 0 -o space /dev/da0s1a
/dev/da0s1a: 3867.2MB (7919964 sectors) block size 16384, fragment size 2048
        using 22 cylinder groups of 183.77MB, 11761 blks, 23552 inodes.
super-block backups (for fsck -b #) at:
 160, 376512, 752864, 1129216, 1505568, 1881920, 2258272, 2634624, 3010976, 3387328,
 3763680, 4140032, 4516384, 4892736, 5269088, 5645440, 6021792, 6398144, 6774496,
 7150848, 7527200, 7903552

# mount /dev/da0s1a /mnt
# cd /mnt
# restore -rv -f /home/guru/myThings/FreeBSD/tinyUsb.dmp
Verify tape and initialize maps
Tape block size is 32
Header with wrong dumpdate.
Dump   date: Tue Aug  5 09:50:36 2008
Dumped from: the epoch
Level 0 dump of /mnt on rebelion.Sisis.de:/dev/da0s1a
Label: none
Begin level 0 restore
Initialize symbol table.
Extract directories from tape
Calculate extraction list.
warning: ./.snap: File exists
Make node ./var
Make node ./var/account
Make node ./var/at
Make node ./var/at/jobs
Make node ./var/at/spool
Make node ./var/audit

the restore is *terrible* slow, aound 200 blocks per second:

$ df -k /mnt ; sleep 60 ; df -k /mnt
Filesystem  1024-blocks Used   Avail Capacity  Mounted on
/dev/da0s1a     3829660  454 3829206     0%    /mnt
Filesystem  1024-blocks Used   Avail Capacity  Mounted on
/dev/da0s1a     3829660  642 3829018     0%    /mnt

Am I doing something wrong?
What means 'Header with wrong dumpdate'?

	matthias
-- 
Matthias Apitz
Manager Technical Support - OCLC GmbH
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