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>> Its more how much i/o rather than the size. If you have a bunch of |
| 2 |
>> stuff swapped out, but it hardly ever needs to be swapped in, the |
| 3 |
>> impact will be low. |
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>> |
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>> Keep an eye on the use with vmstat; |
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>> |
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>> adam@rix ~ $ vmstat 5 |
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>> procs -----------memory---------- ---swap-- -----io---- -system-- |
| 9 |
>> ----cpu---- |
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>> r b swpd free buff cache si so bi bo in cs us |
| 11 |
>> sy id wa |
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>> 0 0 56700 351244 79564 207848 0 0 3 3 11 7 1 |
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>> 0 99 0 |
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>> 0 0 56700 351244 79564 207848 0 0 0 8 52 27 0 |
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>> 0 100 0 |
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>> 0 0 56700 351244 79564 207848 0 0 0 0 45 14 0 |
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>> 0 100 0 |
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>> 0 0 56700 351244 79564 207848 0 0 0 0 47 17 0 |
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>> 0 100 0 |
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>> |
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>> from the man page; |
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>> Swap |
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>> si: Amount of memory swapped in from disk (/s). |
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>> so: Amount of memory swapped to disk (/s). |
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>> |
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>> |
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> Exactly! My system is the same way. |
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> |
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> Right now I've got a 4GB system that's using 708MB swap. But vmstat |
| 30 |
> isn't showing any swap activity. Why? Because some processes that I'm |
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> not aware about because I'm obviously not using, got swapped out a long |
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> time ago, and Linux is using that reclaimed RAM to compile chromium ;) |
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> |
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> If/when I need part of that 708MB becomes active, Linux will swap it |
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> back in in one short burst that I doubt that I'll even notice. |
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|
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Then why not have a really big swap file? If swap is useful as a |
| 38 |
second layer of caching behind RAM, why doesn't everyone with some |
| 39 |
extra hard drive space have a 100GB swap file? |
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|
| 41 |
- Grant |
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