Messages in this thread | | | From | (bill davidsen) | Subject | Re: Blockbusting news, this is important (Re: Why are bad disk sectors numbered strangely, and what happens to them?) | Date | 21 Oct 2003 20:26:56 GMT |
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In article <200310180830.h9I8ULuc000419@81-2-122-30.bradfords.org.uk>, John Bradford <john@grabjohn.com> wrote: | > > BTW: Hard drives apparently use more sophisticated algorithms, | > > involving measuring head signal level even when there is no problem | > > reading the data, and eventually remapping a sector on read before the | > > information is lost. | > > | > | > Which means cat /dev/hda > /dev/null makes sense in | > cron.weekly... | | Indeed. Some drives can also do a timed defect scan using S.M.A.R.T.
You make the point I was going to question, is the cat (dd?) better than a S.M.A.R.T. scan? I would think that the scan would be more likely to be doing some special error checking, like turning off one level of ECC or similar, and might see things a normal read might not. In other words, the difference between no uncorrectable errors and no errors.
I am thinking of something like a C2 scan on a CD, to get error detection without error correction. -- bill davidsen <davidsen@tmr.com> CTO, TMR Associates, Inc Doing interesting things with little computers since 1979. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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