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On Saturday 10 March 2007, mwq <mwq@××.pl> wrote about '[gentoo-user] |
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RAID': |
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> Imagine such a situation: I have two |
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> hard drives but drive A is twice faster when reading and writing then |
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> drive B. I want to make RAID 0 using A and B. Why are the stripes sizes |
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> on both drives excacly the same? |
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If stripe sizes aren't consistent, it's takes hundreds more CPU cycles (and |
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a separate code path) to determine where to write a block. This |
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calculation has to be repeated every time a block is written so, it can |
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easily end up limiting your total throughput by making an I/O operation be |
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CPU bound. |
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> I think that using twice |
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> greater stripe on A gives more speed then using equal stripes. |
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If A is also twice as big, you can do as Dan Farrell suggested to get some |
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increased performance. If A is the same size, you'd be sacrificing speed |
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across the whole raid-ed device to potentially gain some speed in the |
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sections where you can make A's segments bigger. |
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-- |
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Boyd Stephen Smith Jr. ,= ,-_-. =. |
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bss03@××××××××××.net ((_/)o o(\_)) |
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ICQ: 514984 YM/AIM: DaTwinkDaddy `-'(. .)`-' |
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http://iguanasuicide.org/ \_/ |
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New GPG Key! Old key expires 2007-03-25. Upgrade NOW! |
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