IxChariot is a networking workload generator from Ixia. It stresses the network to help predict networked application performance.
You can use the High_Performance_Throughput script workload of IxChariot to simulate the NTttcp workload. The tuning considerations for this workload are the same as those for NTttcp.
For more information on IxChariot, see "Resources" later in this guide.
Performance Tuning for Remote Desktop Services Knowledge Worker Workload
Windows Server 2008 R2 Remote Desktop Services (RDS) capacity planning tools include automation framework and application scripting support that enable the simulation of user interaction with RDS. Be aware that the following tunings apply only for a synthetic RDS knowledge worker workload and are not intended as turnings for a server that is not running this workload. This workload is built with these tools to emulate common usage patterns for knowledge workers.
The RDS knowledge worker workload uses Microsoft Office applications and Microsoft Internet Explorer. It operates in an isolated local network that has the following infrastructure:
Domain controller (Active Directory, Domain Name System—DNS, and Dynamic Host Configuration Protocol —DHCP).
Microsoft Exchange Server for e-mail hosting.
IIS for Web hosting.
Load Generator (a test controller) for creating a distributed workload.
A pool of Windows XP–based test systems to execute the distributed workload, with no more than 60 simulated users for each physical test system.
RDS (Application Server) with Microsoft Office installed.
Note: The domain controller and the load generator could be combined on one physical system without degrading performance. Similarly, IIS and Exchange Server could be combined on another computer system.
Table 12 provides guidelines for achieving the best performance on the RDS workload and suggestions as to where bottlenecks might exist and how to avoid them.
Table 12. Hardware Recommendations for RDS Workload
Hardware limiting factor
Use 64-bit processors to expand the available virtual address space.
Use multicore systems (at least two or four sockets and dual-core or quad-core 64-bit CPUs).
Choose the appropriate RAID configuration. (Refer to “Choosing the RAID Level” earlier in this guide.)
If applicable, set the write-through cache policy to 50% reads and 50% writes.
If applicable, select Enable write caching on the disk through the Microsoft Management Console (MMC) disk management snap-in (Diskmgmt.msc).
If applicable, select Enable Advanced Performance through the MMC disk management snap-in (Diskmgmt.msc).
The amount of RAM and physical memory access times affect the response times for the user interactions. On NUMA-type computer systems, make sure that the hardware configuration uses the NUMA, which is changed by using system BIOS or hardware partitioning settings.
Allow enough bandwidth by using network adapters that have high bandwidths such as 1-GB Ethernet.
Recommended Tunings on the Server
After you have installed the operating system and added the RDS role, apply the following changes:
Navigate to Control Panel > System > Advanced System Settings > Advanced tab and set the following:
Navigate to Performance Settings > Advanced > Virtual memory and set one or more fixed-size pagefiles (Initial Size equal to Maximum Size) with a total pagefile size at least two to three times the physical RAM size to minimize paging. For servers that have hundreds of gigabytes of memory, the complete elimination of the paging file is possible. Otherwise, the paging file might be limited because of constraints in available disk space. There are no clear benefits of a paging file larger than 100 GB. Make sure that no system-managed pagefiles are in the Virtual memory on the Application Server.
Navigate to Performance Settings > Visual Effects and select the Adjust for best performance check box.
Allow for the workload automation to run by opening the MMC snap-in for Group Policy (Gpedit.msc) and making the following changes to Local Computer Policy > User Configuration > Administrative Templates:
Navigate to Control Panel > Display, and disable Screen Saver and Password protected screen saver.
Under Start Menu and Taskbar, enable Force Windows Classic Start Menu.
Navigate to Windows Components > Internet Explorer, and enable Prevent Performance of First Run Customize settingsand select Go directly to home page.
Navigate to Start > All Programs > Administrative Tools > System Configuration Tools tab, disable User Account Control (UAC) by selecting Disable UAC, and then reboot the system.
Allow for the workload automation to run by opening the registry, adding the ProtectedModeOffForAllZones key, and setting it to 1 under:
Minimize the effect on CPU usage when you are running many RDS sessions by opening the MMC snap-in for Group Policy (Gpedit.msc) and making the following changes under Local Computer Policy > User Configuration > Administrative Templates:
Under Start Menu and Taskbar, enable Do not keep history of recently opened documents.
Under Start Menu and Taskbar, enable Remove Balloon Tips on Start Menu items.
Under Start Menu and Taskbar, enable Remove frequent program list from Start Menu.
Minimize the effect on the memory footprint and reduce background activity by disabling certain Microsoft Win32® services. The following are examples from command-line scripts to do this: