Capacity

This article is part of a mini-series. You can find the other articles here. In the previous articles in this series we saw how to calculate a farm’s capacity and then how to determine its load. With that information and knowledge of our methodology we can go about calculating the capacity of the new farm, in other words doing the actual sizing. Which is dead simple, by the way.

This article is part of a mini-series. You can find the other articles here. As we have seen in part 1 of this series, when sizing a new farm the first thing we need to know is the capacity of the existing farm. Armed with data on capacity and additionally load, we can easily calculate the capacity of a new farm. In this article I describe how to determine capacity of the four relevant hardware components of a XenApp server: CPU, memory, storage and network.

This article is part of Helge’s Profile Toolkit, a set of posts explaining the knowledge and tools required to tame Windows user profiles. Setting up a network share on a file server for hosting user profiles is not too difficult if you follow the steps outlined in this article. The recommendations I give here apply to both Windows roaming profiles and Citrix Profile Management (UPM) profiles.

Bugs and Annoyances ICA connections initiated over the ICA client object (ICO) SDK fail because 128-bit encryption cannot be enabled. Apparently, setting EncryptionLevelSession does not work. Annoyingly, this bug is more than a year old, was fixed in the ICA client 10.2 and reappeared in the current version 11.0. Bugs like this one are bad for the entire Citrix ecosystem, because they break cool tools like Citrix Quick Launch, xConnect and others I may not even know about. [Update 2009-09-30: this bug has been fixed in ICA client 11.2.]

Why does Windows 7 feel faster than Vista, although really it is not? Improvements to the graphics driver model (WDDM got upgraded to version 1.1) certainly add to this feeling and reduce the memory footprint of the desktop windows manager (DWM) process. Microsoft describes the changes in its Graphics Guide for Windows 7.

Even with the most meticulous design, the day will come when your farm’s capacity is not sufficient any more. User numbers increase, applications become more resource-hungry and the amount of data to be handled increases steadily. So what do you do? Simply more of the same, i.e. buy more servers and add them to the farm? That is one way of increasing capacity, but it is not the only one and therefore may not be the best.