Ups and downs to the Citrix Reciever:

What’s the upside?
•  The Receiver is the last Citrix client you will ever need to install - The Receiver has a premise based Server component that will act as staging area and control facility for propagating Plugin updates out to the end users. The receiver will periodically check the Server for updates and, provided you allow it, will update with the newer Plugins as they become available.
•    More frequent release of enhancements - Plugins will be released independently and on their own schedules meaning we’ll be able to bring enhancements to market when they are ready without having to wait for a periodic client release.
•    More granular control over what gets installed on the clients - Administrators will be able to control which users get which Plugins and when.
* Note: A standalone Plugins Pack will be made available for those who would like to continue to manage their client updates with existing methods.

What’s the downside?
In order to make room for these changes we need to remove\deprecate some of our legacy features:
1: Thinwire 1 - Thinwire 1 is a low-level graphics virtual channel that was replaced by Thinwire 2 back in MetaFrame 1.8 FR1 (August 2000). Removing TW1 from the Windows client means that you won’t be able to connect to a MetaFrame 1.8 Server with the newer client. See, I told you we were reluctant to remove anything.
2: Program Neighborhood –Program Neighborhood has been around since the early days of WinFrame. PN is a launch pad for XenApp Applications. When launched it connects with the XenApp Server and lists the Apps that are available for the user. PN was effectively replaced by PNAgent (Now the XenApp User Experience Plugin), which provides the same functionality with a far superior interface by integrating the XenApp delivered Apps transparently into the users Desktop. We removed PN from an active enhancement path several generations ago but we’ve been keeping it alive in maintenance mode to give our customers time to move on to the newer and better XenApp Plugin. There is more to the story but I think I’ll post that as a separate Blog entry.

You can read the entire post here.

I personally can’t wait to get my hands on the Citrix Reciever, i have been looking for this product for ages.. i can’t understand why it has taken so long, but i do love the fact that it is just around the corner now.

On a final note i wish you all a happy new year

René Vester

If you guys have anything you think is missing, do let me know. My hope is to make a gathering of technical materials dynamically provided by the vendors and the community.

Rene Vester

But what i got to thinking is.. with all the buzz currently on the Citrix Reciever for iPhone, using the zoom features, navigational features and the like, i am just thinking; would there be similar features to use in the other new phones, based on Windows Mobile etc? With the focus on the Citrix Reciever for iPhone are Citrix remembering to use all the features they can in the new devices like the HTC TouchHD and similar devices? The OS is well known, so it should not be as hard to put the new large touch-screen cellphone features to use.

Chris Fleck just did a blog post asking for input on what applications would be cool to integrate seamless with the iphone, i am sooo looking forward to the Citrix Reciever for iPhone, just hope all the eggs are not in one basket, or we are going to have to shout hard and long for the Windows Mobile client to be improved as soon as we get the iPhone client

Alot of people are doing reviews on the HTC Touch HD vs. iPhone 3G and i think they are both an expression of the Next-Gen mobile devices. So i do think a lot of companies are going to consider basing even more of their application delivery on these mobile devices that finally gives us the monitor we need to use it productively and with no peripherals.

Rene Vester

Citrix has launched a blog and the developers and architects of the Advanced Products group whom are working on the client have started blogging. You can find the blog here: http://community.citrix.com/display/xa/Citrix+Receiver+for+iPhone

Latest question from the developers to us is whether or not we need the Control Characters like Crtl-alt-del-tab and so on for use in the IPhone Client… or plugin..

Rene Vester

Michaels blog can be found here: www.dabcc.com/michaelkeen

I will be keeping up to date, i think it is awesome that someone is covering the more "business technology" kind of things as many others have chosen to focus on the more technical aspects of our virtualization world.

Rene Vester

Back in April 2007 Ruben Spruijt did an awesome technical document, comparing the different approaches available to perform application virtualization. I was super happy to hear the Ruben has been reviewing this material and it is now available to the public in an updated version

Ruben Spruijt provides the document freely available "AS IS" via download from the PQR Showcase site and the document itself can be downloaded here: Application Virtualization Solution Overview and Feature Compare Matrix

I still hope to convince Ruben to do a Webinar for the soon-to-be Danish Citrix User Group(DKCUG)

Hope you guys will take a look, its a great overview and gives invaluable information when it comes to differentiating the different solutions. Ruben also made an announcement on his blog at BrianMadden.com you can visit it Here.

The solutions investigated are:

• Altiris SVS Professional
• Citrix XenApp client-side Virtualization
• Endeavours Application Jukebox
• InstallFree Bridge and Mini Bridge
• Microsoft App-V
• VMware ThinApp
• XenoCode

Rene Vester

The agenda seems to be:

• What’s new in the XenServer™  5 virtualization platform.
• How to provision workloads to physical or virtual servers
• How to use XenServer™  for high availability and disaster recovery
• Best practices for utilizing XenApp™  on XenServer™

There is more information information on Rich Crusco’s blog here: http://community.citrix.com/blogs/citrite/richcr/2008/12/09/Live+Webcast+-+XenServer+5+Technical+Overview

And you can register for the event here: https://www1.gotomeeting.com/register/644940559

Rene Vester

However it hit me, i am going to spend the rest of my life keeping the static pages up to date, so i have been trying to build these pages in a more dynamic way.

It is still a work in progress but have a look in the top menu under technotes or have a click here: http://www.renevester.com/technotes/

Please.. feel free to give input or share your ideas as to what information would help save you time

Rene Vester

So.. ever since Citrix bought XenServer and had their way with it to optimize the virtualization platform for XenApp i have wondered what it is exactly that makes XenApp run better on XenServer.

I have talked to anyone i could think of, poked and prodded everyone i have come in contact with, and the fact is that everyone comes back to Shadow Page Tables. this is the technology that makes Citrix XenApp perform better on XenServer than other Hypervisors. And more than that, the memory allocated  on the host to build these Shadow Page Tables.

So how to describe the Shadow Page Tables memory, George Dunlap did a good explanation in Anil Madhavapeddy’s blog post:

"The hypervisor allocates a certain amount of memory for each VM to use for shadow page tables; this is called shadow page table memory. As new page tables are created and old ones aren’t used anymore, the hypervisor cycles through this shadow page table memory. When it needs a new page and there isn’t enough, it will ‘unshadow’ the guest page tables that haven’t been used for the longest time to reclaim shadow memory, so that it can use more."

"We don’t know ahead of time how much shadow memory a given workload will use, but we can estimate based on the amount of memory that the VM has. We allocate enough shadow memory for each page to be mapped once, more or less, then add an extra 50% to have some slack. For all the workloads we’ve tested, that’s been enough – except XenApp."

"XenApp is the one workload we’ve found that requires more shadow page table memory than our standard default. Because XenApp generally starts hundreds of copies of the same process, the same memory ends up mapped in hundreds of different processes. What happens when all of those processes are active is that XenServer is continually unshadowing one process’ page tables in order to shadow another process’ pagetables; only to have to re-shadow the original ones a second or two later when it runs again! This is called thrashing, when there’s not enough of a limited resource."

So.. as this was located to be the issue, Citrix did a nice fix for this problem. In XenServer 4.1 they introduced what we all know as the "Optimized for XenApp" template in XenServer.. I for one always wondered what the f… that Shadow Multiplier number was good for. So.. what i have learned, maybe you all knew, is that the Shadow Multiplier is the amount of memory dedicated to allow Shadow Page Tables for a Virtual Server.

So, in conclusion, the Shadow Multiplier available on XenServer templates could actually be used for tuning of other workloads to provide better performance. And naturally, Terminal Servers should benefit almost as much as XenApp servers.. i am assuming Citrix has done other tweaks as well..

Anil Madhavapeddy’s blog was my first lead and after that i have been trying to dig deeper as i would love to be able to better explain the reasons for why XenApp runs better on XenServer. I have not been able to find any technical descriptions or get in contact with people who could explain further, but i will continue to dig deeper, as i personally have had enough of the Vendor-Specific whitepapers which more than anything else, promotes that specific vendor, not the strength or weaknesses in different areas. So .. Georg Dunlap or similar, if you are out there, give me a shout

If you want to read more in depth about Page Tables and the way Memory in virtualized machines work have a look at Anil’s Blog post.

/Rene Vester

So what is inside the Paint by numbers kit for webinterface customization? Well there is a description on how to turn your webinterface into en easier on the eye colorscheme. What i did was to take my standard normal 5.0 webinterface and paint it white. So now it looks like this:

I added my company’s logo through the standard management console and i now have a more neutral webinterface. It is in my oppinion a lot easier on the eye and alot easier to get in sync with the company colors and branding. Citrix provided new graphics for the animated loading page so that everything fits the same scheme.

As always everyone wants their webinterface to fit their personal needs, so this means that Webinterface is constantly in focus when it comes to nationalizing. And earlier Brian Madden updated a list of language-packs supplied for Webinterface, but i couldnt seem to find it when i was looking just now.

However i did a simple danish translation of the first major things, and i am leaning towards not translating the error messages as it will mostly confuse the administrators and the supports.

The files needed to edit and create your own language files are all placed in C:\program files\citrix\Web interface\languages.

The end result for me is this, when it comes to danish, this could be in any language that makes more sense to you

Give it a try, if you guys are interested i will gladly host a list of files with reference to the translator for each set of language files.

Rene Vester

________________________________________________________________

References:

PimpMyXenApp
My Home Lab