Red Hat Bugzilla – Bug 215535
The network speed from xen0 to HVM guest is slow
Last modified: 2007-11-30 17:07:37 EST
Description of problem: From Intel: -------------------------------- In the testing for RHEL5 Beta2 M5 we found that the network speed from xen0 to hvm guest is very slow. The highest speed is 1.8MB/s and the lowest is 20KB/s, the average is 200KB/s. And Guest==>Xen0 is about 2MB/s, it's also slow . In unstable tree, the speed should be at least more than 5MB/s. -------------------------------- They also reproduced on M9. In my own testing on i386, I saw nothing of the sort; I saw ~7MB/s from dom0 to domU, and ~4MB/s from domU to dom0. So this may be hardware dependent. Version-Release number of selected component (if applicable): How reproducible: Steps to Reproduce: 1. 2. 3. Actual results: Expected results: Additional info:
Is this with qemu? If so please try again with the PV netfront driver. qemu drivers are known to be slow due the high emulation overhead.
The PV driver isn't currently part of the baremetal RHEL5 kernel. Yes you can build it for RHEL5 without rebuilding the entire kernel. While SMP and 32/64 support may indeed be lacking at this point in time, they're being addressed upstream. On the other hand, there really isn't much that can be done to bring qemu performance to the level of PV performance.
For all practical purposes, if you care about performance you should be using a PV kernel with RHEL5.