App-V
W7 w. BC Enabled Windows Vista Windows XP
Table 2 Average Results for Scenarios
Windows 7 Advantage over Windows XP
63% 68% 76% 69% 26%
Windows 7 Advantage over Windows Vista
63% 65% 79% 55% 15%
Bandwidth
Windows 7 11.50 7.72 13.29 9.46 50.1
Windows XP 22.53 22.80 31.71 22.97 66.48
Windows Vista 22.45 22.91 28.50 17.14 67.16
Windows 7 Advantage over Windows XP
49% 66% 58% 59% 25%
Windows 7 Advantage over Windows Vista
49% 66% 53% 45% 15%
Downloading and launching an application (Microsoft PowerPoint 2010), deployed with App-V had a 26 percent advantage over Windows XP and a 15 percent advantage over Windows Vista. Bandwidth savings were 25 percent as compared to both older
operating systems (Table 3, Page 25).
Table 3 Average Results for App-V Scenario
App-V
Time
Windows 7 401.96
Windows XP 541.00
Windows Vista 472.72
Windows 7 Advantage over Windows XP 26%
Windows 7 Advantage over Windows Vista 15%
Bandwidth
Windows 7 50.1
Windows XP 66.48
Windows Vista 67.16
Windows 7 Advantage over Windows XP 25%
Windows 7 Advantage over Windows Vista 25%
As can be seen in Table 2 and Table 3, the effect of BranchCache on file download time is significant enough in productivity savings, but the effect on bandwidth can have the greatest effect on operational cost savings.6
Scenarios
The sections below provide summaries of the effect of Windows 7 with BranchCache enabled for each of the five test scenarios. The data upon which these summaries are based is presented in the appendices. All of the tests in these scenarios were performed using the set of test conditions described in the lab configuration section. These tests included both asymmetric and symmetric WAN emulation. Asymmetric networks are typical of those provided by DSL and cable networks. In these networks, the download speed is usually greater than the upload speeds.
Since the results of BranchCache acceleration for both Hosted and Distributed cache modes were very similar and the performance of Windows XP and Windows Vista were also similar, the charts only show some of the results of the testing. This choice was made so that the charts would be easier to read. Detailed results tables can be found in the appendices.
Test Scenario 1 – CIFS/SMB File Accesses
The CIFS/SMB File Access Test consists of file downloads initiated from within
Microsoft PowerPoint 2007 for files on a network share (mounted as Drive N). The times were based upon the time required to open the file.
Results
The following charts show the average performance comparison between Windows 7 with BranchCache enabled versus the performance of Windows XP and Windows Vista.
The Average Bandwidth Used chart (Figure 11, Page 27) and the Average Download Time chart (Figure 12, Page 27) show that Windows 7 with BranchCache enabled requires much less time and bandwidth than either Windows Vista or Windows XP. It should be noted that Windows Vista had improvements in CIFS/SMB protocol
processing, which is shown by the better performance of Vista over XP.
The two charts on the following pages show the results of acceleration on CIFS/SMB file downloads. The charts show that downloads to XP or Vista clients take consistent amounts of time 7 and use the same bandwidth for each client transfer, and that Windows 7 with BranchCache greatly accelerates the download.
The different test conditions – network speed and latency – have a definite effect on the speed of all the transfers: slower speeds require longer transfer times (Figure 13 - SMB Test Results: Transfer Time, Page 28). The test conditions have no effect on Windows 7 bandwidth utilization, as can be seen by the overlap for all Windows 7 results (Figure 14 - SMB Results: Bandwidth Utilization, Page 29). Also clearly seen is the BranchCache effect on speed and bandwidth, with markedly sharp falloffs in both metrics.
The download time for Windows 7 Distributed Mode for the Symmetrical 5 Mbps WAN condition does not show as great a savings, as the faster network speed shortened the time required for the initial file download, while the shortest and most accelerated download time approached the limits of the available bandwidth for all three WAN conditions.
7 The slightly shorter time illustrated for the third client is an anomaly of chart preparation. For clarity purposes, only the first of two test runs for the first three clients was selected for the chart.
For the SMB scenario, the performance of the third client was slightly faster than for the previous two clients. The fourth and fifth clients and second test run were more consistent than this particular download instance.
Figure 12 - Average Bandwidth Used:
CIFS/SMB Protocol (Smaller is better)
Figure 12 - Average Download Time:
CIFS/SMB Protocol (Smaller is better)
Figure 13 - SMB Test Results: Transfer Time
Figure 14 - SMB Results: Bandwidth Utilization
Test Scenario 2 – HTTP File Downloads
The HTTP File Access Test consists of file transfers initiated from a page hosted on an HTTP or web server.
Results
The chart, Average Download Time (Figure 15, Page 30) illustrates the 63 percent time savings delivered by Windows 7 with BranchCache over the nearly identical download times (see appendices for details) required by Windows Vista and Windows XP.
The bandwidth savings for Windows 7 with BranchCache enabled showed savings of 49 percent as compared to the bandwidth required by Windows Vista or Windows XP (Figure 16, Page 31).
Figure 15 - Average Download HTTP Protocol (Smaller is Better)
The following two charts show the results of acceleration on HTTP file transfers (Figure 17 - HTTP Test Results: Transfer Time, Page 32 and Figure 18 - HTTP Test Results:
Bandwidth Utilization, Page 33). The charts show that file downloads to Windows XP or Windows Vista clients take consistent amounts of time and use the same bandwidth for each client transfer, and that Windows 7 with BranchCache greatly accelerates the file download.
The different test conditions – network speed and latency – have a definite effect on the speed of all the file downloads: slower speeds require longer transfer times. This is evident for the 5 Mbps downloads for Windows Vista where the download time is less than half for the slower networks. It also is apparent with the faster initial client
performance for Window 7 with BranchCache enabled. The acceleration provided by BranchCache is not as profound over the faster network, at least for a file size that is small relative to the connection speed.
The test conditions have no effect on BranchCache bandwidth utilization, as can be seen in the near total overlap of the BranchCache results. BranchCache is equally efficient across the full range of test conditions utilized in this study.
Figure 16 - Average Bandwidth Used: HTTP Protocol (Smaller is better)
0 20 40 60 80 100 120 140
1 2 3
Time in Seconds
Clients