Re: [Bug-ddrescue] Slowdown after ~1 hour

[Franc Zabkar]

When you replaced the HSA, did you transfer the adaptives of the donor HSA 
to the patient drive? There are parameters such as MR bias, microjogs 
(spacing between read and write elements), and preamp gains that differ 
between drives. These values are written to the "ROM" on the PCB.

Otherwise, if your drive had already begun to degrade before the HSA was 
damaged, then there is a "slow fix" solution which disables relocation and 
certain aspects of error correction at the firmware level (by editing 
modules 02 and 32 in the reserved service area on the platters).

Scott Dwyer's HDDSuperTool has scripts which implement this "fix":
http://www.sdcomputingservice.com/hddsupertool

Headstack matching for Western Digital:
http://www.hddoracle.com/viewtopic.php?f=86&t=1036&p=4555

The following article explains why your drive did not survive the power 
supply failure and how you can "fix" the faulty overvoltage protection on 
your other WD drives so that they will survive future overvoltage events.

Catastrophic failures in Western Digital PCBs:
http://www.hddoracle.com/viewtopic.php?f=59&t=1119&p=5033

-Franc Zabkar