with AWS, your system is sharing the vendors virtual machine environment with other customers, and performance is pretty much out of your control.
I found no strange processes or queries while load average was at peak. IO also didn't change. Some more slow queries were logged, but not many.
I think sharing the VM with other customers doesn’t have much to do with this. I checked my other servers too, and only those that have postgresql have the load average issue. Generally it doesn’t impact my system much, but when there are slow queries, this issue just makes everything worse.
Hi,
generally speaking AWS is pretty good at isolating users (and you can request single tenancy machines or
dedicated machines as well if you're concerned about this).
However, if you're running t1 or t2 instances, you get the concept of CPU credits. When those run out, your
system is slowed down until the credits recover. I could imagine that this way some cyclic load patterns
emerge, if there is constant load on the machines.
Nhan, what instance types are you running?
Bye,
Chris.
