After 15 days of using ddrescue nonstop, a mixture of boredom, curiosity, and desperation has finally made me seek further information.
The failing HDD is a 1TB SATA seagate and is about 5 years old. There is no obvious hardware failure. I didn’t drop the drive, the PSU didn’t burn out or anything. There’s no clicking noise, so unless some dust got into it or maybe some capacitor fried, I have no idea what could have caused this. It was pretty spontaneous with no warning signs. Windows cannot start with the drive plugged in, however Linux can see the disk listed as OK, though it says it has 26648 bad sectors.
I immediately began ddrescue and after about 15 days was able to get 50% of the data rescued, however when it started it’s second pass (reverse), it slowed down drastically. Specifically it alternates between 32768 B/s and 21845 B/s.
Through googling, I’ve found that these values are somewhat common, but I was unable to find out why. (A user on this forum has an almost identical issue, though I was able to get more data on the first pass and I'm direct SATA. https://forums.gentoo.org/viewtopic-p-7722742.html)
I’ve tried restarting ddrescue, shutting my pc down for a while to let it cool off, changing sata ports, but restarting from the mapfile once again leaves me at a transfer rate of 32768 B/s and 21845 B/s. Before the second pass I was getting an average of 600kbs. Far from ideal, but compared to this, I'm dying to return.
Are the values 32768 B/s and 21845 B/s specific enough to pinpoint why the drive is acting up? And if so, are there any parameters to try that would fix this specific rut? I tried –min-read-rate but it just causes it to make bigger leaps, it will never exceed beyond 32768 B/s. Sadly undoing the reverse with the -R parameter gave me even worse results. Nothing but read errors at a rate of 3kb. I quickly undid that and now I'm back to 32kb and 21kb.
Although it's still rescuing data, the speed is just too absurd. Would it even be worth seeking professional services at this point? I fear that the price of recovery will be more than I can afford right now and I can’t imagine walking in with what I have and asking for a service discount for getting 50% of the data rescued myself, lol. However, knowing that there are proprietary tools out there, maybe it would be worth letting them do it at this point so I can have some peace of mind. Otherwise I guess all I can do is leave this thing running for a year. Would anyone happen to have an estimate of what I would be paying in this situation?
Otherwise if anyone has experience with ddrescue, I'd appreciate any advice. So far I have 0 bad sectors and 0 bad areas with 2583MB non-trimmed.