AnsweredAssumed Answered

What does reported host memory congestion really mean?

Question asked by johndesha on Feb 19, 2015
Latest reply on May 14, 2016 by felicitybowden

Many of my hosts often report memory congestion, and I am trying to find out what vmturbo considers "congestion."  In one cluster my hosts average 75% memory usage and there is no congestion reported, while another averages 35% and does report it.

 

So I tried an experiment.  I have a relatively new ESXi cluster that I am still migrating VMs to, and utilization is at about 20% (memory). After applying patches, half of the hosts currently have no VMs on them. The other hosts are at 40-52% memory and are all reporting memory congestion in vmturbo. I put the empty hosts into maintenance mode, waited a little while, and the remaining hosts are no longer reporting memory congestion.

 

So, is congestion a metric, or just a flag indicating there could be better VM balancing across the cluster?  How do others use this information and what do you do about it?

 

Thanks!

Outcomes