Mobility express high memory usage

[jmprats]

I have a ME installation. The controller is a AP-3800 8.10.112 and there are 23 AP's and 5 WLAN's. In normal operation memory is at 84% and with 60 clients shared between all the AP's the controller memory is at 90% and it stops serving clients on the controller AP.

I have rebooted the Master AP and disabled Application Visibility. Now memory is at 78%.

Is this high memory usage normal?

I can read in the datasheet that Cisco Aironet 3800 ME can support 16 WLAN, 100 AP's and 2000 clients and that "If there are more than 25 Access Points in a Mobility Express network, the Master AP(running the Wireless LAN controller function) can service a maximum of 20 clients. This limit only applies to Master AP and not any other Access Point in the Mobility Express network".

I don't reach those limits by far.

Do I need to change configuration?

[rrudling]

Always take those published scaling limits with a pinch of salt :) (they tend to be based on best case scenarios with absolute minimum of features so assume reality will always be worse, sometimes much worse)
There's an open bug https://www.cisco.com/c/en/us/td/docs/wireless/access_point/mob_exp/810/release_notes/b_ME_RN_810.html#open-caveats
Table 4. Open Caveats in Release 8.10.121.0
CSCvt31668 8.10: Efficient Join fails because of low memory
Do you have efficient join enabled? Although not clear that disabling it will help but clearly they're aware of a memory problem.
There are a number of unresolved memory bugs - 3 examples:
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvh03883
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvm81198
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvc55590
So I'd say upgrade to 8.10.121.0 to make sure you've got all available fixes, turn off AVC and DNAC and SNMP.
But judging by all these bugs memory problems do seem to be 'normal' so you might want to think about using EWC on a 9100 AP instead (it will still support 3800 APs).

[jmprats]

I have Efficient Join enabled, I will try to disable it and I amb going to upgrade to 8.10.121

I think I need SNMP because I am creating guests users from Cisco Prime

DNAC? I think I don't use it

Migrating to EWC on 9100? I was thinking about it, but a little afraid about a technology even newer than Mobility Express, but sure I am going to consider it and do some testing

[m.yildiz]

Hi Community,

i have the same issue. 

I disabled the avc and efficient join, but memory usage is still 78%, on 2802i and 3802i.

I am running the 8.10.130.0 Version.

Thanks in advance for any further Information

[jmprats]

Hi. I think something like 80% must be considered as normal. While you don't arrive to 85% or 90% you won't have problems in performance