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On Tue, Oct 26, 2010 at 8:49 AM, Iain Buchanan <iaindb@××××××××××××.au> wrote: |
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> Hi, |
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> |
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> over the last week or so I've noticed unusually large swap usage. I |
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> usually hibernate this laptop and have uptimes up to 12 days so apps can |
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> run for a long time. I don't usually use any swap space (except for a |
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> few k). |
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> |
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> If I swapoff and swapon, the usage falls back to zero but then creeps up |
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> again over a few days. |
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> |
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> $ free -m |
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> total used free shared buffers cached |
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> Mem: 3040 859 2181 0 38 415 |
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> -/+ buffers/cache: 406 2634 |
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> Swap: 494 431 62 |
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> |
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Looking at above values 494MB does not seem to be enough for |
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hibernation. Do you add extra swap or close some apps before |
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hibernation? |
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|
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If your system trying to fill up your swap while you have more than |
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2GB of main memory available, only thing I can think of is your |
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swapiness is set very high. You check and alter is as follows |
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|
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$ cat /proc/sys/vm/swappiness |
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and |
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# echo N > /proc/sys/vm/swappiness |
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|
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where N is a value between 0 and 100. Higher number means more |
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swapping. If I had 3GB of ram I would set it to something closer to 0 |
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or even 0 if I am just gonna use it for hibernation. |
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|
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> nothing unusual there, except for the swap usage itself. 'top' doesn't |
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> show any large apps. sorted by mem the top 4 are: |
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> PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND |
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> 8318 iain 20 0 494m 150m 21m S 0 5.0 1:20.67 evolution |
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> 20424 iain 20 0 342m 77m 30m S 0 2.5 0:01.84 firefox |
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> 8009 root 20 0 83364 37m 6260 S 7 1.2 38:34.31 X |
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> 8090 iain 20 0 159m 32m 1600 S 1 1.1 3:48.08 skype |
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> |
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> Hm, I just noticed Mem is in %. % of what? % total or % used? Even if |
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> it was % of total RAM that could be as much as 152Mb for evo and 76Mb |
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> for firefox. Not that much really. |
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> |
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% of total main memory excluding swap because its rather difficult to |
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take it into account. |
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3040*0.05 = 152 evolution |
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> any ideas? |
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> |
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|
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You can try to view swap usage on top by pressing f then p and enter |
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and sort by it by F then P and enter. The values wont be very |
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realistic though. Alternatively you could try is to compare resident |
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memory usages before and after swapoff. |
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|
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Given the mem usage of your apps, total mem usage looks normal. What |
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does not seem normal is that swap inclined mem usage. Seriously take a |
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look at your swapiness value. The default value cannot be right every |
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particular case. |
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> thanks :) |
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> -- |
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> Iain Buchanan <iaindb at netspace dot net dot au> |
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> |
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> Chuck Norris once skewered a man with the Eiffel tower. |
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> |
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> |
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> |
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-- |
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Fatih |
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