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 […]
In the previous post we saw two images one showing the QOS curve as advertised by the python API (image 1) and the other generated by a standalone python script (image 2) Image 1 Image 2 In this post I will cover how we worked out the cost for each I/O size and the associated […]
The SolidFire array is primarily used as an ISCSI target and allows for quality of service on a per volume basis. You can read more about it here. The purpose of these posts are to talk about the QOS functionality and how we can look to monitor this on the Arrays. Some Background.. Recently we […]
I have been recently working on the Meltdown and Spectre bugs and assessing what the impact will be to our servers. As part of this testing we used a tool called SLOB which we use to stress memory accesses (cached reads) and also I/O based on random and sequential I/O. The database in use was […]
Overview In this post we will take a look at Ports the data is gathered by the statport command. We can view different metrics when parsing the data from this command including iops, throughput, latency and queuing. Cache statcmp Cpu statcpu Hosts statvlun / statvlun -hostsum / -vvsum Ports statport -host Volumes statvlun -vvsum Getting […]
