Jan Engelhardt <[EMAIL PROTECTED]> wrote: >On Dec 27 2006 19:09, Paul Slootman wrote: >> >>This works fine, but I noticed that quite some time was being used by >>the mdX_raid1 threads; even on a partition that's not even being used at >>this time... (it was an empty mounted filesystem, but I umounted it to >>be sure the filesystem code wasn't causing some IO). >> >>My question is: why is CPU being used by the RAID1 threads, even for >>those devices that are otherwise unused? What are they doing? > >First-time synchronization (if applies), otherwise I suspect some >housekeeping (bitmap perhaps?).
No, I had rebooted after the initial synchronization was complete. >Otherwise it seems like a question who does what. On a raid5 array (i.e. >cpu-heavy), both smbd and mdx_raid5 accumulate time for, of course, xor >calculation. On those devices that are actually in use, I'd understand CPU being used; but where the device is not even mounted or used for swap or whatever, I find that amount of CPU usage very high for just checking the bitmap... I may take the idle device apart and reassemble without a bitmap to see whether that makes any difference. Paul Slootman - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
