Download Using virtualization to enforce real-time Thesis

Design
Diploma Thesis
Appendix D Scheduling test on Fedora Core 11 shows the results of this test on Fedora Core
11 without virtualization, thus proving that Fedora couldn't have been used as a reference
system for this test.
With one virtual machine
The test has been run five times on one virtual machine running Xenomai. The worst results
are:
[0, 10[
[10, 100[
[100, 1K[
[1K, 10K[
[10K, 100K[
[100K, 1M[
0
997 518 966
2 463 507
9 635
7 364
528
[1M, 10M[
[10M, 100M[
[100M, 1G[
[1G, 10G[
[10G, 100G[
[100G, ∞[
0
0
0
0
0
0
Table 3-13:
Scheduling test on one virtual machine
63
E
-0
1
1,20
9,
1,00
0,80
0,60
E
10
11
[
5,
7,
M
K[
,1
00
[1
00
K
,1
0K
[1
Figure 3-19:
-0
3
-0
3
E
-0
4
E
30
0K
,1
K
[1
,1
00
[1
[
K[
0[
10
[1
0,
,1
[0
9,
0,
0[
0,00
2,
00
38
E
E
+0
0
0,20
-0
2
0,40
Distribution of the normalized approximate influence (1 VM)
Like without virtualization, bound95% = 100 ticks = 44.1 ns. The order of magnitude is still the
same. We can conclude that ESXi doesn't generate any significant latency for the
processor when running one virtual machine. (The virtual machine doesn't have to wait to
get the possibility to run.)
Moreover, the variation between the best and the worst case is very small. Thus it can be
said that the way one virtual machine is scheduled by ESXi on the processor is very
predictable.
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Diploma Thesis-RT&Virtualization-V1.0/30.04.2010
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