Em 26/11/2010 15:29, Tejun Heo escreveu: > Hello, > > On 11/24/2010 06:00 PM, Greg Freemyer wrote: >>>>> HI, I'm trying to recover data from a damaged hard disk, which has >>>>> plenty of bad sectors, but also has many good ones. The problem is that >>>>> when a bad sector is found, the drive keeps trying to read it, instead >>>>> of giving up and just move on, so the average data read rate is around >>>>> 5Kb/s. With such rates, it will take more than an year to finish. Since >>>>> I'm using gnu ddrescue (which logs bad sectors, so one can try then >>>>> again later), my goal is not waste time with errors, leaving the retries >>>>> to a second round. >>>>> So, my first attempt was to drastically lower the timeouts in >>>>> libata-eh.c. It seems to have improved a little, but I'm not having more >>>>> than 12Kb/s. >>>>> Is there any way to minimize retries and make errors finish faster? > You can directly issue r/w commands using SGIO where you can control > retry and timeout explicitly. Hmm... it might be a good idea to allow > userland to set FAILFAST bit on a block device? Sounds like a great idea to me. I think it would become popular in forensics. I followed Artem Bokhan s' tip on timeout and tried Greg Freemyer s' on smartctl. Unfortunately this particular drive is only ATA-7, so scterc wasn't available. But is definitively good to know. I never played with SGIO before, but there is plenty of time to learn to use it before ddrescue can finish copying.:) Thank you all, Atila -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
