[Bug-ddrescue] Newbie question -- how to copy longer before splitting after restarting?

[Eric Stout]

Thank you very much for ddrescue.  I'm new to it but finding it very useful.  I'm using version 1.9 of ddrescue with a RIP Linux LiveCD to get what I can from two NTFS partitions on an old 160GB WD1600JB that's failing.  (It sounds like a bad spindle or bearings to me.)

The drive stops responding after a short while.  To make that while a bit longer, I have installed it into an aluminum USB2 & Firewire enclosure and stored it in the fridge.  When I work with it, I move the bad drive in the enclosure into the freezer and access run RIP Linux and ddrescue from a notebook just outside the fridge.  In this way I can read 2 to 8 GB before the drive stops responding. 

One problem is that when the drive stops responding and Linux can no longer see the failing drive, ddrescue is still in it's first pass of copying, at an average rate of around 6MB/sec.  When the drive stops responding, ddrescue decides that the rest of the drive or partition is one gigantic error.  I exit ddrescue, confirm that the OS can no longer see the drive, and then power off the bad drive.  When I later restart ddrescue (using the same logfile) it immediately starts splitting errors.  Unfortunately it rarely proceeds any faster than 64KB/sec. 

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My primary question is ... how can I restart ddrescue so that it starts copying quickly from where it was when the failing drive stopped responding, rather than splitting errors slowly from there? 
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If I'm making any other obvious mistakes, I welcome your comments on those and other tips as well.

Thank you,
Eric