IIS 7 and Above
ASP Session State server high CPU utilization
Last post Feb 13, 2018 09:21 AM by Yuk Ding
Feb 06, 2018 01:26 PM|RoniIT|LINK
I'm administrating IIS 10 Web Farm with 3 servers and 1 session state server (StateServer mode).
Sometimes, during high load on the web servers the CPU utilization become 90-100% on session state server and our site performance decrease dramatically.
Today, I increased load on web servers via JMeter in order to see web server and session state servers behavior, but they work properly.
My question is why ASP session state utilize 90 % CPU with 5000 user and sometime 5% with 7000 users?
How to troubleshoot ASP Session State service?
Feb 07, 2018 06:40 AM|Yuk Ding|LINK
How long cookie time out did you set ? In state server, asp.net pipeline will not dispose the session so frequent like it in in process session mode. In addition, state server mode require the object to be serialized and deserialized so it will require more
machine resource. If all the things just works fine, maybe it only depend on how may concurrent serialization operation are there in asp.net session state service.
Feb 08, 2018 06:49 AM|RoniIT|LINK
Thank for response.
The cookies time out is set 20 minutes. I realize that in state server mode the server recourse utilization is higher, but the issue is that when web server connections becomes 10.000 state server sometimes serve them with 5% CPU, sometime 90-100% CPU.
I don't know how troubleshoot session state server. I can't find any log and etc. it is like black box.
thank you in advance.
Feb 13, 2018 09:21 AM|Yuk Ding|LINK
You could try the steps in this link: