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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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> |
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> |
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> 1. swap is good. Unless you have a good reason, leave it there. You do not |
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> have a good reason to remove it and neither does anyone else. |
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> |
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> 2. Don't use the swap that you have. It's slow. It is not a replacement for |
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> RAM. |
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> |
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> 3. If you use a little bit of swap, 100-200MB, that's fine. It's also a sign |
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> you need more RAM. |
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> |
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> 4. If you're using all your RAM and a couple of GB of swap, you're screwed. |
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> Avoid this. |
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> |
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> 5. Swap that you never write to or read from never needs to hit the drives. |
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> If you're worried about drive wear, turn off logging. |
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> |
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> kashani |
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|
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OK, how about I enable a 512MB swap file and keep an eye on it. As |
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long as I'm not using more than 200MB, I'm not suffering from disk |
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swap slowdown, right? |
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|
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- Grant |
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