Friday, December 16, 2016

VMware's View Storage Accelerator, just use it....

Originally named Content Based Read Cache (CBRC) when it was introduced in vSphere 5 starting in 5.0, VMware's View Storage Accelerator is a read caching solution that is supported in VMware View 5.1 and above that offers improved performance by caching common image blocks in RAM when reading virtual desktop images.  All this is completely transparent and can be used with other Storage Array technologies.

CBRC has been a great addition to the VMware architecture and offer's some real benefits to those looking to offload storage requests without additional products or costs.  Since the most common blocks are cached in memory and there is no need to request those blocks from the storage infrastructure, there is a reduction in overall storage traffic particularly during boot storms.

The following test data showing the reduction in IOPS and storage bandwidth was posted by VMware on their End User Computing Blog:

Screen shot 2012-05-01 at 9.46.48 AM

However, View Storage Accelerator does have some limitations:

1.) It's a read only caching technology.  

The write IOPS still have the same heavy impact as before.  If you take away boot storms, write IOs are usually estimated to be between 50-80% of the total IOs during steady state virtual desktop operation.  

2.) It's limited to 2GB of RAM per host.  

It is a dynamic cache, but in today's age of relatively cheap server DRAM, this is starting to seem a little limited.  I'm sure 2GB was determined at one time to be a maximum "sweet spot" for resource usage versus benefits gains.  However, since I run primarily linked clone non-persistent desktops in my environment, I wonder how fast a desktop could be if say 16GB of the desktop's main replica image could be cached in RAM.

Thursday, February 4, 2016

VMware preparing "Enabling the Digital Enterprise" announcements on February 9

Preregister for the VMware's February 9 announcements. This is continuing their trend from last year where it's kind of an in-between VMworld's mid-year major product announcements webcast.

From VMware:

Look for two exciting components: 
1) Enabling the Digital Enterprise: Deliver and Secure Your Digital Workspace
     Pat Gelsinger will be joined by Sanjay Poonen who will present VMware’s digital workspace vision and share exciting announcements that help companies securely deliver and manage any app on any device. 
2) Enabling the Digital Enterprise: Build and Manage Your Hybrid Cloud
     Raghu Raghuram joins Pat Gelsinger to share how VMware’s software-defined approach can help simplify how you build and manage your hybrid cloud.

Friday, January 15, 2016

Teradici CTO clarifies Tera1 Zero Client support in the future

A while back I received a response from Randy Groves from Teradici to my concern that Tera1 Zero clients were no longer officially supported after Horizon View 6.0.1.  It turns out that they will still work as before (at least through View 6.2) with their final 4.7.1 firmware, they just won't be getting any new features that will be added to the Tera2 Zeros.  His response follows:

As the Teradici CTO, let me add a little color to this discussion. When support for Network Appliances (e.g. Cisco, F5,...) was added to the protocol (back in View 5.x), this created a new authentication scheme to allow these devices to be an authorized-man-in-the-middle. We did not have the ability to support both the old and the new authentication scheme in the Tera1 devices so they stayed on the "old scheme". Starting with Horizon 6, VMware is only certifying clients that use the new authentication scheme and have not indicated that they will add any new capabilities nor provide support for clients that use the old scheme (which includes older software clients, too).
Because of the large install base of older clients, I do not expect that they will disable the old authentication mode. Since they are not doing any new feature development in that mode, they are also unlikely to break compatibility. However, fixing any issues that might arise for "old mode" clients is not committed by either Teradici or VMware. which is why we have made this End-of-Life announcement.
Tera1s have been on the market for 8 years and we stopped selling new chips to our partners 3 years ago. You will notice in the KB that we are providing "technical guidance" until December 2016 which will give everyone at least 5 years of guidance even if you were one of the last customers to buy a Tera1. Even as CTO, I have several Tera1 devices in my various offices (in fact I am using one right now). I am running pre-released code that is even beyond Horizon 6.1.1. I fully expect that they will continue to work well beyond December 2016. However, if you need new Horizon features or the new capabilities in Tera2 devices, then you will need to upgrade. If you need a guarantee that your Tera1 devices will continue to work on future Horizon releases, then you should also upgrade. Or, you can just keep using them until a Horizon release comes out that breaks compatibility with the old authentication mode - if and when that occurs.
We just want to be clear about the facts so you can make an informed decision.
Randy Groves - Teradici CTO