Those of you attending VMUG (VMware User Group) meetings in the US recently may have come across the guys from Proximal Data. They were at the Austin & Silicon Valley VMUGs & I believe they may even have had the key-note at the San Diego VMUG. I had the pleasure of meeting up with Rich Pappas (VP of Sales and Business Development) and storage veteran Rory Bolt (CEO) at VMware’s Partner Exchange this year. They gave me an overview of their new Autocache 1.1 features.
I was first introduced to Raxco Software when I wrote an article on the vSphere Storage Blog related to fragmentation on Guest OS file systems. In that post, I wanted to highlight some side effects of running a defragment operation on the file system in the Guest OS (actually, primarily the Windows defragger). Raxco reached out to say that they had a product that would actually prevent fragmentation occurring in the first place, which was rather neat I thought. Bob Nolan, Raxco’s CEO reached out to me again recently to let me know about a new product that they were launching on the market (on April 23rd, 2013). If you’re looking for a solution to reclaim dead space from within a Guest OS, then read on.
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 users, this is not an area of concern and is probably a benefit. But there are some concerns.
Last week, I had a chance to catch up with Brady Murray and Rex Walters of Tintri. Mostly this was a transfer of information, but the guys let me know that they are on the verge of announcing a new per-VM replication feature which they first demoed to me when I met Tintri at VMworld last year. This will be the main feature in Tintri’s new 2.0 launch.
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 I/Os can be sent to a disk. In the case of vSphere environments, where many hosts can be doing I/O to the same shared disk device, it can be helpful to throttle the LUN queue depth from time to time when congestion arises. In this post, we will compare and contrast Adaptive Queues with Storage I/O Control (SIOC).