Re: [Bug-ddrescue] Bug-ddrescue Digest, Vol 102, Issue 4

[William]

Hello.

Patch was sucessfully applied and seems to work perfectly. Now I'm 
testing patched DDrescue.


##Generating an image from a damaged HDD with patched DDrescue:

ddrescue -vvv -n -d -c 1 --no-reverse-pass /dev/sdc Toshiba-160GB.dd 
Toshiba-160GB.dd.log


GNU ddrescue 1.18.1
About to copy 160041 MBytes from /dev/sdc to Toshiba-160GB.dd
    Starting positions: infile = 0 B,  outfile = 0 B
    Copy block size:   1 sectors       Initial skip size: 128 sectors
Sector size: 512 Bytes
Max retry passes: 0
Direct: yes    Sparse: no    Split: no    Trim: yes    Truncate: no

Press Ctrl-C to interrupt
Initial status (read from logfile)
current position:     2536 MB,     current sector: 4953649
 last block size:   157505 MB
rescued:     2536 MB,  errsize:   53760 B,  errors:     105

Current status
rescued:     2569 MB,  errsize:   70656 B,  current rate:        0 B/s
   ipos:     2569 MB,   errors:     138,    average rate:     124 kB/s
   opos:     2569 MB, run time:    4.43 m,  successful read: 1 s ago
Copying non-tried blocks... Pass 1 (forwards)


##Generating an image from a damaged HDD which was previously running 
with unpatched ddrescue:

ddrescue -vvv -d -c 1 -r1 --skip-on-first-err   /dev/sdb 
Samsung-1500GB.dd Samsung-1500GB.dd.log


GNU ddrescue 1.18.1
About to copy 1500 GBytes from /dev/sdb to Samsung-1500GB.dd
    Starting positions: infile = 0 B,  outfile = 0 B
    Copy block size:   1 sectors       Initial skip size: 128 sectors
Sector size: 512 Bytes
Max retry passes: 1
Direct: yes    Sparse: no    Split: yes    Trim: yes    Truncate: no

Press Ctrl-C to interrupt
Initial status (read from logfile)
current position:   941701 MB,     current sector: 1839260429
 last block size:     1493 MB
rescued:     1450 GB,  errsize:    796 MB,  errors:  824393

Current status
rescued:     1450 GB,  errsize:    796 MB,  current rate:        0 B/s
   ipos:   941727 MB,   errors:  824505,    average rate:    62967 B/s
   opos:   941727 MB, run time:    5.26 m,  successful read: 1 s ago
Copying non-tried blocks... Pass 1 (forwards)


Best regards.


PS: Why not creating a patch that only runs forwards with just one pass, 
at least when using --no-retry; something like "-n --only-forwards"? 
Would be hard to create it?


Em 07-07-2014 13:00, address@hidden escreveu:
> Send Bug-ddrescue mailing list submissions to
>         address@hidden
>
> To subscribe or unsubscribe via the World Wide Web, visit
>         https://lists.gnu.org/mailman/listinfo/bug-ddrescue
> or, via email, send a message with subject or body 'help' to
>         address@hidden
>
> You can reach the person managing the list at
>         address@hidden
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Bug-ddrescue digest..."
>
>
> Today's Topics:
>
>     1. Re: Bug-ddrescue Digest, Vol 102, Issue 1 (Scott Dwyer)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Sun, 06 Jul 2014 16:57:29 -0400
> From: Scott Dwyer <address@hidden>
> To: address@hidden
> Subject: Re: [Bug-ddrescue] Bug-ddrescue Digest, Vol 102, Issue 1
> Message-ID: <address@hidden>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> On 7/6/2014 3:02 PM, William wrote:
> > These new features will help to insert DDrescue in professional and
> > forensics environments (mainly --no-reverse-pass). In such
> > circumstances, the program must to do exactly we ask it to do.
> > Automated behaviour is suitable for newbies.
> Since everybody is so excited about the --no-reverse-pass option, I
> think I need to explain exactly what it does and does not do more clearly.
>
> Ddrescue 1.18.1 does the copy phase in 3 passes. The first pass is
> forward with skipping, second pass is reverse with skipping, and third
> pass is forward with no skipping (everything is opposite of that if
> starting out in reverse). Then the trimming and splitting phases are
> done in multiple passes (it goes by error sizes so there is no set
> number on how many passes, but splitting in 1.18.1 has lots of head
> movement).
>
> The --no-reverse-pass option only makes the second copy pass go the same
> direction, so the head jumps back to beginning for the pass. The copy
> phase still makes 3 passes.
>
> If you want the control, make the skip size 0 (--skip-size=0). As
> Antonio has already stated in another thread, this is how to make it do
> the copying phase in one pass.
>
> After the copying phase, there will still be the trimming and splitting
> phases. My new options will make each of those only do one pass each
> (MUCH more important for head movement than no-reverse).
>
> So even if you use skip-size=0 and my --trim-sequentially and
> --split-sequentially options, there will still be 3 total passes
> (copying, trimming, and splitting).
>
> If you want to do everything all in one pass (total control), you need
> --skip-size=0 --cluster-size=1 which will read sector by sector from
> start to finish. These options already exist without my help.
>
> Scott
>
>
>
> ------------------------------
>
> _______________________________________________
> Bug-ddrescue mailing list
> address@hidden
> https://lists.gnu.org/mailman/listinfo/bug-ddrescue
>
>
> End of Bug-ddrescue Digest, Vol 102, Issue 4
> ********************************************