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Am Samstag, 21. März 2009 19:39:08 schrieb Jarry: |
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> And one more counter-argument: with traditional partitions I can select |
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> where a certain partition is (physically). Those partitions accessed |
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> frequently I put to the beginning of the disk with higher transfer-rate. |
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> In my case, it makes quite difference: |
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> |
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> obelix ~ # hdparm -t /dev/md2 |
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> Timing buffered disk reads: 252 MB in 3.02 seconds = 83.23 MB/sec |
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> |
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> obelix ~ # hdparm -t /dev/md9 |
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> Timing buffered disk reads: 150 MB in 3.02 seconds = 49.72 MB/sec |
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Who says you'd loose that ability with LVM? You could |
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1) Create two md devices and put one volume group on top of each calling them |
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vg-fast and vg-slow, then put your logical volumes into either VG. |
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2) Keep your setup with 9 md devices and put one large VG on top, then for |
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each LV tell LVM on which physical volume (PV) it should reside (don't know |
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wether that really works, though. Just guessing that this is what the |
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"PhysicalVolumePath" in lvcreate is meant for, the man page leaves it open). |
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Bye... |
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Dirk |