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Florian Philipp wrote: |
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> Hi! |
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> |
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> I've got two questions concerning LVM2. |
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> |
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> Number one: What stripesize parameter would you use? The manual of my |
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> mainboard advises to use 64k for a RAID-0. Would that be useful for my |
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> portage tree or a more conventional partition like /usr and /var? |
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> |
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> Number two is not really a performance issue but it's LVM2-related: |
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> LVM2-mirrors need an extra log device but the man pages don't tell anything |
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> about how large it has to be or if it can be a partition or loop device on |
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> the same hdd as one of the mirrors. |
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> |
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> Thanks in advance! |
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> |
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> Florian Philipp |
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|
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Sizing I/O subsystems is highly workload and filesystem dependent, and |
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there's really no such thing as a one-size-fits-all quick answer. There |
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are models and there are some really good I/O subsystem benchmarks you |
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can use once you know what your workload characteristics are. |
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|
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I highly recommend the book "Storage Network Performance Analysis" |
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http://www.amazon.com/Storage-Network-Performance-Analysis-Huseyin/dp/076451685X/ |
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for the tools to do this. But one thing you can do first is to run your |
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workload on a system and capture data with "iostat". If you don't have |
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"iostat", you'll need to emerge "sysstat". The "iozone" benchmark is in |
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Portage, as is bonnie++. The I/O benchmark I like most is IOMeter, but |
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that requires a Windows system to run the control console and |
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downloading a Linux agent from their web site. |
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-- |
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