QLogic – Execution Throttle Feature Concerns

I had a customer reach out to me recently to discuss VMware’s Storage I/O Control behavior and Adaptive Queuing behavior and how it works with QLogic’s Execution Throttle feature. To be honest, I didn’t have a good understanding of the Execution Throttle mechanism from QLogic so I did a little research to see  if this feature inter-operates with VMware’s own I/O congestion management features.

Heads Up! Device Queue Depth on QLogic HBAs

Just thought I’d bring to your attention something that has been doing the rounds here at VMware recently, and will be applicable to those of you using QLogic HBAs with ESXi 5.x. The following are the device queue depths you will find when using QLogic HBAs for SAN connectivity: ESXi 4.1 U2 – 32 ESXi 5.0 GA – 64 ESXi 5.0 U1 – 64 ESXi 5.1 GA – 64 The higher depth of 64 has been this way since 24 Aug 2011 (the 5.0 GA release). The issue is that this has not been documented anywhere. For the majority of…

QLogic Mt. Rainier Technology Preview

I was fortunate enough yesterday to get an introduction to QLogic’s new Mt. Rainier technology. Although Mt. Rainier allows for different configurations of SSD/Flash to be used, the one that caught my eye was the QLogic QLE10000 Series SSD HBAs. These have not started to ship as yet, but considering that the announcement was last September, one suspects that GA is not far off. As the name suggests, this is a PCIe Flash card, but QLogic have one added advantage – the flash is combined with the Host Bus Adapter, meaning that you get your storage connectivity and cache accelerator…