Re: [Bug-ddrescue] Need help - ddrescue very slow - avg 27kb/s

[me]

Hi,

Not so good news. The current rate went down to 32kb after a while. I
checked fdisk again and it reported that the problem harddisk has invalid
partition. Disconnecting and reconnecting the USB cable will bring up the
current rate to 20MB/s for a while. Any idea how I can sustain the current
rate of 20MB/s without disconnecting and connecting the harddisk USB
cable?

ddrescue status:

Press Ctrl-C to interrupt
Initial status (read from logfile)
rescued:   253107 MB,  errsize:       0 B,  errors:       0
Current status
rescued:   255922 MB,  errsize:       0 B,  current rate:    32768 B/s
   ipos:   255922 MB,   errors:       0,    average rate:     799 kB/s
   opos:   255922 MB,     time from last successful read:       0 s
Copying non-tried blocks...


Fdisk -l :

Disk /dev/sdf: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x6058418b

Disk /dev/sdf doesn't contain a valid partition table
address@hidden:~/Desktop/ddrescue-1.13/ddrescue-1.13# ./ddrescue -n
/dev/sdf /media/sdc1/rescue.img /media/sdc1/rescue.log

Thanks.

regards,
Ridzham

> Thanks Reon but I don't think it's a problem.
>
> I've disconnect the problem harddisk and connect it again without changing
> any configuration. Did the ddrescue again and the current rate went up to
> 20MB/s (which is much faster than 27kb/s).
>
> I'm very happy that the speed has very much improved. However, I noticed a
> difference when I did a fdisk -l. It showed multiple partitions in the
> problem hard disk. It used to have only 1 NTFS partition which was
> corrupted. Any comments?
>
> Disk /dev/sdf: 500.1 GB, 500107862016 bytes
> 255 heads, 63 sectors/track, 60801 cylinders
> Units = cylinders of 16065 * 512 = 8225280 bytes
> Disk identifier: 0xf6f93598
>
>    Device Boot      Start         End      Blocks   Id  System
> /dev/sdf1               1          63      506016   82  Linux swap /
> Solaris
> /dev/sdf2             152       60801   487171125    7  HPFS/NTFS
> /dev/sdf3   *          64         126      506047+  83  Linux
> /dev/sdf4             127         151      200812+  83  Linux
>
> regards,
> ridz
>
>
> "Reon Toerien" <address@hidden>
>
>
>
>
>
>> On 10 January 2011 04:39, "Reon Toerien" <address@hidden>wrote:
>
>> I would not connect the drives via USB, I always prefer to connect
>> directly
>> via PATA/SATA.
>>
>> On 10 January 2011 02:33, <address@hidden> wrote:
>>
>>> Hi Andrew,
>>>
>>> Tried your suggestions. There's marginal improvement current rate
>>> increased to 32kb but alternates with 21kb which makes the average
>>> about
>>> 27kb too.
>>>
>>> Initial status (read from logfile)
>>> rescued:     1702 MB,  errsize:       0 B,  errors:       0
>>> Current status
>>> rescued:     1713 MB,  errsize:       0 B,  current rate:    21845 B/s
>>> ipos:     1713 MB,   errors:       0,    average rate:    27198 B/s
>>> opos:     1713 MB,     time from last successful read:       0 s
>>>
>>>
>>> Both source and destination are attached externally thru USB.
>>>
>>> I did a hardware test with Seagate tool and it did not report any
>>> problem.
>>>
>>> regards,
>>> Ridz
>>>
>>>
>>>
>>> > Hi Ridz.
>>> >
>>> > Maybe try not specifying cluster size?
>>> >
>>> > You can interrupt the current run since you have a log file.  Try
>>> running:
>>> >
>>> >  ./ddrescue --v /dev/sdc /media/sde1/rescue.img
>>> /media/sde1/rescue.log
>>> >
>>> > Maybe using synchronous or direct may help (-vDd or -vd or -vD).
>>> Beyond
>>> > that, maybe it's a hardware issue.   How are the source and
>>> destination
>>> > drive attached to the computer?
>>> >
>>> > Andrew
>>> >
>>> >
>>> >
>>> >
>>> > --- On Sun, 1/9/11, address@hidden <address@hidden> wrote:
>>> >
>>> > From: address@hidden <address@hidden>
>>> > Subject: Re: [Bug-ddrescue] Need help - ddrescue very slow - avg
>>> 27kb/s
>>> > To: address@hidden, address@hidden
>>> > Received: Sunday, January 9, 2011, 5:16 PM
>>> >
>>> > Hi Andrew,
>>> >
>>> > Thanks for replying. I was initially recovering to an NTFS
>>> filesystem.
>>> The
>>> > average rate never went higher than 27kb. I've read that writing a
>>> large
>>> > file to NTFS filesystem can get progressively slower. Therefore, I
>>> > formated my recovery harddisk to ext3. However, there was no
>>> improvement
>>> -
>>> > the average rate is still 27kb and the current rate never go beyond
>>> 30kb.
>>> >
>>> > For the recovery harddisk, I had formatted it following the
>>> instructions
>>> > at
>>> >
>>> http://www.idevelopment.info/data/Unix/Linux/LINUX_PartitioningandFormattingSecondHardDrive_ext3.shtml
>>> >
>>> > Result of mount of the recovery harddisk:
>>> > /dev/sde1 on /media/sde1 type ext3
>>> > (rw,nosuid,nodev,relatime,errors=continue,data=writeback)
>>> >
>>> > regards,
>>> > Ridz
>>> >
>>> >
>>> >> Hi Ridz.
>>> >>
>>> >> What do you mean by "I've formatted it to type 83".
>>> >>
>>> >> Did you just change the partition type or did you actually format
>>> the
>>> >> filesystem?  I ask because writing a large file to an NTFS
>>> filesystem
>>> >> can
>>> >> get progressively slower.  If you just changed the partition type,
>>> that
>>> >> will have no effect on the filesystem at all.
>>> >>
>>> >> In another terminal, type
>>> >> mount
>>> >>
>>> >> and post the output.  That will show what devices are moutned and
>>> what
>>> >> filesystem is in use.
>>> >>
>>> >> Regards,
>>> >>
>>> >> Andrew Zajac
>>> >>
>>> >>
>>> >>
>>> >> --- On Sat, 1/8/11, address@hidden <address@hidden> wrote:
>>> >>
>>> >> From: address@hidden <address@hidden>
>>> >> Subject: [Bug-ddrescue] Need help - ddrescue very slow - avg 27kb/s
>>> >> To: address@hidden
>>> >> Received: Saturday, January 8, 2011, 9:59 PM
>>> >>
>>> >> Hi,
>>> >>
>>> >> Need help. I've ran ddrescue for a few days and it only rescued 10G
>>> out
>>> >> of
>>> >> 500GB. I've tried various command of ddresue but I find the average
>>> rate
>>> >> to be very slow as compared to other examples that I've read in the
>>> >> archives. I've installed ddrescue 1.8 and 1.13. I'm new to Linux and
>>> I'm
>>> >> not sure which version I'm using now. I've also formated my recovery
>>> >> harddisk to ext3 in hope that the speed would increase. But
>>> >> unfortunately
>>> >> it didn't.
>>> >>
>>> >> My hard disks configs are as follows:
>>> >>
>>> >> Problem drive : /dev/sdc  500GB NTFS - Windows detected it as
>>> >> unallocated
>>> >> Recovery drive: /media/sde1  1TB ext3 - I've formatted it to type 83
>>> >>
>>> >> Command:
>>> >>
>>> >> ./ddrescue --no-split --cluster-size=1024 /dev/sdc
>>> >> /media/sde1/rescue.img
>>> >> /media/sde1/rescue.log
>>> >>
>>> >> Current status:
>>> >> rescued:   226559 kB,  errsize:       0 B,  current rate:    27594
>>> B/s
>>> >> ipos:   226559 kB,   errors:       0,    average rate:    27431 B/s
>>> >> opos:   226559 kB,     time from last successful read:       0 s
>>> >>
>>> >> Is there anyway for me to speed up the process.
>>> >> Please help. Thanks.
>>> >>
>>> >> regards,
>>> >> Ridz
>>> >>
>>> >>
>>> >>
>>> >>
>>> >>
>>> >>
>>> >>
>>> >>
>>> >>
>>> >> _______________________________________________
>>> >> Bug-ddrescue mailing list
>>> >> address@hidden
>>> >> http://lists.gnu.org/mailman/listinfo/bug-ddrescue
>>> >>
>>> >>
>>> >>
>>> >
>>> >
>>> >
>>> > _______________________________________________
>>> > Bug-ddrescue mailing list
>>> > address@hidden
>>> > http://lists.gnu.org/mailman/listinfo/bug-ddrescue
>>> >
>>> >
>>> >
>>>
>>>
>>>
>>> _______________________________________________
>>> Bug-ddrescue mailing list
>>> address@hidden
>>> http://lists.gnu.org/mailman/listinfo/bug-ddrescue
>>>
>>
>>
>>
>> --
>> Kind Regards
>> Reon Toerien
>> __________________
>> PO Box 540 Ballito 4420 South Africa
>> Tel: +27 (0) 83 270 2889
>> email: address@hidden
>>
>
>