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On 7/21/2011 4:53 PM, Grant wrote: |
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> So swap isn't treated exactly like RAM. It actually has special |
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> handling in Linux which makes it beneficial to have on almost any |
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> Linux system? According to Alan, things get very bad when a Linux |
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> system hits swap. How can behavior like this be beneficial: |
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> |
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> "When a linux machine hits swap, it does so very aggressively, there |
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> is nothing nice about it at all. The entire machine slows to a |
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> painstaking crawl for easily a minute at a time while the kernel |
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> writes pages out to disk, and disk is thousands of times slower than |
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> RAM. |
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> |
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> It gets so bad that you can't even run a shell properly to try and see |
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> what's going on and kill the actual memory hog." |
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> |
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> Also, aren't you likely to wear out your hard disk sooner using swap? |
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1. swap is good. Unless you have a good reason, leave it there. You do |
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not have a good reason to remove it and neither does anyone else. |
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2. Don't use the swap that you have. It's slow. It is not a replacement |
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for RAM. |
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3. If you use a little bit of swap, 100-200MB, that's fine. It's also a |
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sign you need more RAM. |
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4. If you're using all your RAM and a couple of GB of swap, you're |
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screwed. Avoid this. |
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5. Swap that you never write to or read from never needs to hit the |
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drives. If you're worried about drive wear, turn off logging. |
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kashani |
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