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Linux running slow with 0 swap left

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http://unix.stackexchange.com – Our Linux server is responding very slow. Top command doesn’t show any excessive CPU usage. But I observe that even though there’s about 5GB free memory, system is using all of swap with no free swap left. Could this be reason for system running slow as in there being too many processes. Any solutions you may advise other than reducing the number of processes? Secondly, even though there is free memory available, why is Linux switching on to swap already? I thought swap is used only when there’s not actual memory left. free -m total used free shared buff (HowTos)

Danial's picture
Submitted by Danial on 06/25/2012

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I have been getting requests from application teams that the server is running slow. I have checked the memory utilization, processes running and cpu utilization. Please find below:

#free -m total used free shared buffers cached Mem: 3006 2994 11 0 6 171

Hi All,

I have a RAM of around 11 gig and swap of around 18 G in my Linux Server.

But at some times , I find that All the RAM and 5 gig of swap is used in server...and i also got some advice from our discussion forums to increase the RAM .

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top - 10:33:43 up 133 days, 17:00, 1 user, load average: 0.05, 0.03, 0.05 Tasks: 170 total, 1 running, 169 sleeping, 0 stopped, 0 zombie Cpu(s): 2.1%us, 0.5%sy, 0.0%ni, 97.2%id, 0.0%wa, 0.0%hi, 0.2%si, 0.0%st Mem: 24726100k total, 8255368k used,

on my linux system I get these stats from top:

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Lets say I have 8 GB RAM.

Hi.

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