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Old 09-01-2014, 01:39 AM   #1
procfs
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used swap is 0 on some servers


Hi, I am bit confused and was trying to get an answer by googling but not what I want... any how below is my question

I have few some servers and I can see some machines using swap and some dome (swap is 0) never changes. Whey is this deference.

Bot are using RedHat linux and 64bib

Thanks and Regards
 
Old 09-01-2014, 02:41 AM   #2
EDDY1
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Maybe the work load isn't as heavy on those machines. How much ram is in your machines?
On themachines that don't swap how much of the ram is being used?
 
Old 09-01-2014, 03:12 AM   #3
procfs
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Hi EDDY1, yes work loads are different, one with 0 swap is an oracle database and other one is oracle application server. IBM blades with 16Gb each

Regards
 
Old 09-01-2014, 03:20 AM   #4
EDDY1
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I would say to check memory usage on both. And yes workload makes a difference. Also swap doesn't get used until there isn't any memory to use.
How much swap are you using percentage wise. If almost all of it then you might want to increase the amount of swap you have.
 
Old 09-01-2014, 03:48 AM   #5
procfs
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It goes up to about 30% and stops, this happens during the course of 2 days after a reboot and varies + or - 1% or so. Then again DB server always stays at 0 and never movies. If I to suspect some one has stopped swapping how do I go about investigating since swappiness set at 60 (this is default I think)

Regards
 
Old 09-01-2014, 05:16 AM   #6
EDDY1
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Try turning on
Quote:
swapon
 
Old 09-01-2014, 10:52 AM   #7
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It is possible (haven't use Oracle in years) that oracle locks memory for its own use, and prevents it from being paged out.
 
Old 09-01-2014, 09:30 PM   #8
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Start at top command maybe?
 
Old 09-11-2014, 07:37 AM   #9
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Hi All thanks for the replies but swap is on and swap usage is 0. I am planning on loading one of this server that is running with swap 0 and see if this would change anything

Thanks and best regards
 
Old 09-11-2014, 04:29 PM   #10
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Oracle may not use more ram than set to in config.
 
  


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