We are using a single-server, single-bucket memcached couchbase server instance running on Windows Server 2012 R2 as caching solution of our system for a while. We were running CouchBase version 3.0.3 until last week without issues. Then we had some connectivity issues after installing latest Windows updates and we observed that those updates can run fine with 5.1.1 so we decided to upgrade to 5.1.1.
Before the upgrade the VM was working with stable CPU 10-20% CPU utilization. After the upgrade it started hitting 100%. As an initial workaround we increased the cores of the VM from 4 to 8 which granted some margin of free CPU but still it was around 70-80%.
We are observing the CPU usage on that machine for almost a week and CPU usage never ever gets below 50-60%, sometimes hitting 90%. Below is the PRTG graph that shows CPU usage for the last 30 days. You can clearly see how it peaked after upgrade and settled down a bit after increasing cores.
I’ll attach the memcached task resource usage image to the second post as I’m not allowed to post 2 images in a post as a new user
I’d appreciate if you can assist on how to troubleshoot the issue.