2960 high memory utilization

[Pacerfan9_2]

I noticed on the 2960 switches we have deployed that are running the latest IOS, 12.2(58)SE2, memory utilization is really high (almost 80 percent). I have not noticed any side effects but I wanted to verify this is acceptable. My question is does the high memory utilization matter? I see this may be related to bug CSCtw83946 but no resolution is mentioned.

I did some testing various IOS revisions and below is what I have found using a WS-C2960-48TC-L with default configuration and only my laptop connected to a switchport in vlan1. You will notice memory utilization will grows with each version but jumps drastically with 58. One difference with 58 I needed to use a different command to retrieve memory utilization. The output was gathered by pasting the output of the show command into the Cisco Output Interpreter on their website.

IOS	Show Command	Output
c2960-lanbasek9-mz.122-35.SE5.bin	show memory	Processor memory utilization is 17.26835%
c2960-lanbasek9-mz.122-44.SE6.bin	show memory	Processor memory utilization is 24.76673%
c2960-lanbasek9-mz.122-50.SE4.bin	show memory	Processor memory utilization is 33.52498%
c2960-lanbasek9-mz.122-53.SE1.bin	show memory	Processor memory utilization is 37.51366%
c2960-lanbasek9-mz.122-58.SE2.bin	show memory processor statistics	Processor memory utilization is 76.27979%

[Leo Laohoo · Accepted solution]

I've used all but one of the IOS you've listed in your table.

And the one that I've given a "thumbs up" is NOT listed, 12.2(55)SE7.  All my 3750E/X and 3560E/X are running this IOS without any issues, even though I'm using 802.1x.

[Pacerfan9_2]

I tried 12.2(55)SE7 on the 2960 switch and the Processor memory utilization is 66.42% Areyou seeing anything like this?

[Leo Laohoo]

I've got a few stacks of 2960S (4 switches in a stack) and running 802.1X to all ports.  The memory and processors are running good.  No high CPU or memory utilization.

[lcd_shouldit]

Hi LEO，can you tell me how did you test the IOS stable or not? :)

Sent from Cisco Technical Support iPhone App

[Leo Laohoo]

Hi LEO，can you tell me how did you test the IOS stable or not? 

My switches are running PoE and 802.1X.  It's more than enough to stress the OS.

So I load them up to around 100 stacks and randomly check the syslogs for any crashes or Tracebacks. 

[lcd_shouldit]

Hi LEO , Are you kidding ? 100 stacks ? what do you mean 100 stacks ?

[Leo Laohoo]

Hi LEO , Are you kidding ? 100 stacks ? what do you mean 100 stacks ?

Yes, why?  I have more than 100 stacks but each stack has betwen 2 to 4 switches in a stack.

I have >100 sites and each sites has a distribution cabinet that goes to the other cabinets. 

[Pacerfan9_2]

I am glad to hear 12.2(55)SE7 on the 3560-X is working well for you. I will be implementing our first round of the 3560-X soon and was planning on going with 12.2(55)SE7.

I did some additional testing and the 2960S has more DRAM and utilization does not go quite as high with the 12.2(58)SE2, however 12.2(55)SE7 looks best overall.

Leo, thanks for the feedback you have provided. I am leaning towards using 55 on the new round of 2960S's I will be implementing. Then I will decide if I want to move our existing switches to 55 as well.

IOS	Show Command	Output
WS-C2960-48TC-L		64MB DRAM
c2960-lanbasek9-mz.122-35.SE5.bin	show memory	Processor memory utilization is 17.26835%
c2960-lanbasek9-mz.122-44.SE6.bin	show memory	Processor memory utilization is 24.76673%
c2960-lanbasek9-mz.122-50.SE4.bin	show memory	Processor memory utilization is 33.52498%
c2960-lanbasek9-mz.122-53.SE1.bin	show memory	Processor memory utilization is 37.51366%
c2960-lanbasek9-mz.122-55.SE7.bin	show memory	Processor memory utilization is 65.76735%
c2960-lanbasek9-mz.122-58.SE2.bin	show memory processor statistics	Processor memory utilization is 76.27979%
WS-C2960G-48TC-L		64MB DRAM
c2960-lanbasek9-mz.122-58.SE2.bin	show memory processor statistics	Processor memory utilization is 81.08457%
WS-C2960S-24TS-L		128MB DRAM
c2960s-universalk9-mz.122-58.SE2.bin	show memory processor statistics	Processor memory utilization is 47.53199%
WS-C2960S-48TS-L		128MB DRAM
c2960s-universalk9-mz.122-53.SE2.bin	show memory	Processor memory utilization is 34.73529%
c2960s-universalk9-mz.122-55.SE7.bin	show memory	Processor memory utilization is 36.23788%
c2960s-universalk9-mz.122-58.SE2.bin	show memory processor statistics	Processor memory utilization is 46.8732%