The Design and Implementation of the Anykernel and Rump Kernels

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treecp
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Figure 4.18:
regular file.
Performance of a journaled FFS with the file system on a
As expected, journaling does not affect writing one large file, since a majority of
the operations involve data and not metadata (earlier, we quoted the figure 98.5%
of the operations). In the directory write test a rump kernel still outperforms the
regular kernel. As above, we conclude this is due to better prefaulting of metadata
in the rump kernel backend.
4.6.6 Backend: Networking
We measured the latency of ICMP pinging the TCP/IP stack on common virtualization
technologies. The ping response is handled by the TCP/IP stack in the
kernel, so there is no process scheduling involved. Since User Mode Linux requires
a Linux host, the test against UML was run on Linux. We ran the Xen test with
Linux dom0/domU as well.