I use mpstat a lot and at times want to know if a numa node is busy or at times a specific core. Previously I would post process the mpstat data after comparing the data to the output of lscpu. A while ago I wrote a perl script to map this out and reworked this […]
Recently I had been asked to look at some performance issues on a bunch of VMs which were showing increased write latency. But how do you know where the VM is sending it’s I/O in such a distributed system? With VSAN the compute resource for a VM could be on one server where all I/O […]
Hi as I have had a lot of traffic for the 3PAR performance I have added a short video below on how to import and use the overall Array Performance views.
Hi as I have had a lot of traffic for the 3PAR performance I have added two videos below on how to setup the host and array views which covers hosts and volumes. When looking at the performance data for the volumes you may notice that these are spiking in nature this is down to […]
In my previous posts I have shown how the SolidFire Array QOS implements QOS on a per volume basis. As I was looking for a new project I asked myself could I write a similar QOS program which runs on a virtual machine? I wondered could I dynamically change the Linux built-in QOS(throttling) which is […]
In the previous post I showed how we can work out the QOS values from the average I/O size for a volume. In this post I will show a tool which was created to help monitor if a volume is at its QOS limit. As a quick reminder from the previous post if we look […]
I have been looking a lot at ESX performance and today I was looking at network stats. I can get network data in two second samples from esxtop however parsing of the data is cumbersome. I could use powershell however in this method I need to do a delta from two sets of data where […]