Messages in this thread |  | | Date | 3 Nov 2002 17:08:23 -0000 | | From | linux@horizon ... | | Subject | Re: [lkcd-general] Re: What's left over. |
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Just to complicate things, consider this setup:
# cat /proc/swaps Filename Type Size Used Priority /dev/md5 partition 999864 16904 0 /dev/md6 partition 999864 16924 0 /dev/md7 partition 999864 16920 0
Those are all RAID-1 mirrors, a measure whose ass-saving value I have enjoyed.
While a crash dump to just half of one of those mirrors is fine, finding it might be a little bit tricky. And the fact that the kernel reassembles the mirrors automatically on boot might make retrieving the data a little bit tricky, too.
(After a crash, the mirrors will be inconsistent, so one will get copied over the other, but I'm not too clear on which direction it'll happen in.)
I can't NOT reassemble at least some mirrors on boot because / is mirrored!
Now, to that, add the case that each of those is significantly smaller than main memory. (2/3 size would still allow swap = 2*ram.)
The problem is that hardware is getting more and more sopisticated and requiring ever more elaborate device drivers. Eventually you have to have a cutoff and say that something is too complex to talk to after a crash, even though it's theoretically available. Where is that line? USB? iSCSI? This situation?
A reasonable fallback is to just drop in a cheap crappy dedicated IDE drive for catching crash dumps, but I'd like the crash dumper to know how to wake it up from sleep mode; I'd hate to leave it spinning all the time... - 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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