Storage I/O Control

What’s new in vSphere 6.5 Core Storage

Hello from VMworld EMEA in Barcelona. Well, we can finally talk about vSphere 6.5 today. In this post, I want to highlight a number of new and enhanced [...]

New mclock I/O Scheduler in vSphere 5.5 – Some details

My colleague Duncan wrote a post relatively recently around the new mclock I/O scheduler which VMware introduced in vSphere 5.5. He also mentioned some caveats [...]

Does Storage DRS work with Adaptive Queuing?

Many of you will be aware that Storage DRS uses Storage I/O Control (SIOC) for load balancing based on I/O metrics. However a statement in one of our white [...]

Adaptive Queueing vs. Storage I/O Control

This post is to look at two different technologies available in vSphere to manage the queue depth on your ESXi host(s). A queue determines how many outstanding [...]

Why is the siocActiveTimePercentage counter only ever 0% or 100%?

Last week I published a blog article about new performance counters in vSphere 5.1 for monitoring Storage I/O Control (SIOC). Soon after publishing, I received [...]

Monitoring Storage I/O Control activity with new vSphere 5.1 counters

There was an interesting question posted recently around how you could monitor Storage I/O Control activity. Basically, how would one know if SIOC had kicked [...]

vSphere 5.1 Storage Enhancements – Part 8: Storage I/O Control

Storage I/O Control (SIOC) was initially introduced in vSphere 4.1 to provide I/O prioritization of virtual machines running on a cluster of ESXi hosts that [...]