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Am 11.06.2014 22:17, schrieb thegeezer: |
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> On 06/11/2014 07:57 PM, Stefan G. Weichinger wrote: |
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>> looks promising: |
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>> |
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> |
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> awesome. i did have a look through the diff, there are lots of scsi |
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> drivers selected, storage (block) cgroups but i think the crucial factor |
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> was the HZ was set at 100 previously and 1000 now. i guess it has |
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> helped kernel-io though maybe a kernel hacker in here might give a more |
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> authoritative answer |
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The help suggests to choose 100 for servers ... the 1000 comes from the |
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sysresccd-setup, yes. |
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I wonder if chosing the "Processor Family" also had an influence. |
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And I even wonder more if I have some bad choices in my desktop's kernel |
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as well ;-) it's a grown setup over years ... |
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For now it looks good ... I will configure the current kernel as a |
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fallback kernel and maybe play with some options. |
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>> One big fat hw-RAID10 might be better? |
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>> But losing the wrong 2 drives makes it crash again ... afaik. |
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> yeah you could argue with raid6 you can _only_ lose two disks, whereas |
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> if you lose the right disks with raid01 you can lose 3 and still rebuild. |
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> raid 0+1 (as opposed to raid10, slightly different) gives you great |
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> speed and at least one drive you can lose. |
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> however, you are not protected by silent bit corruption but then you are |
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> using btrfs elsewhere. |
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... for the OS, yes ... and maybe for the target of virt-backup. |
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> myself i would use lvm to partition and then at least you can move |
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> things around later; btrfs lets you do the same afaiu |
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> _always_ have your hotspare in the system, then it takes less time to |
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> come back up to 100% |
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> nothing is quite as scary as having a system waiting on the post and a |
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> screwdriver before rebuild can even start |
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good suggestion, sure. |
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That would mean rebuilding the arrays to a RAID6 over 4 or 5 disks and |
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keeping one aside. |
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>> time for a break here. |
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> i'd strongly recommend such monitoring software as munin to have running |
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> -- this way you can watch trends like io times increasing over time and |
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> act on them before things start feeling sluggish |
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I will take a look into it and check how much time I need to learn and |
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set up. |
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> well earned break :) |
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;-) |
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S |
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