Some benchmark figures for Xen paravirtualized guests

These are not really meaningful ... but you would like to see them anyway, right ? Test were made on the XenTestEnvironment .

iozone

Two iozone tests were run in parallel on two guest systems running on top of the same hypervisor: the hosting machine has only one disk ... so both guests were writing through Xen Virtual Block Device to it simulanously

SLC3:

[root@lxxen0-u0 root]# iozone -M -c -e -w -i0 -r256k -s1g -t10 -F /tmp/d{1,2,3,4,5,6,7,8,9,0}
        Iozone: Performance Test of File I/O
                Version $Revision: 1.1 $
                Compiled for 32 bit mode.
                Build: linux

        Run began: Thu Nov 23 18:25:53 2006


        Machine = Linux lxxen0-u0 2.4.21-47.0.1.EL.cernxenU #1 SMP Wed Nov 22 08:48:09  Include close in write timing
        Include close in write timing
        Include fsync in write timing
        Setting no_unlink
        Record Size 256 KB
        File size set to 1048576 KB
        Command line used: iozone -M -c -e -w -i0 -r256k -s1g -t10 -F /tmp/d1 /tmp/d2 /tmp/d3 /tmp/d4 /tmp/d5 /tmp/d6 /tmp/d7 /tmp/d8 /tmp/d9 /tmp/d0
        Output is in Kbytes/sec
        Time Resolution = 0.000001 seconds.
        Processor cache size set to 1024 Kbytes.
        Processor cache line size set to 32 bytes.
        File stride size set to 17 * record size.
        Throughput test with 10 processes
        Each process writes a 1048576 Kbyte file in 256 Kbyte records

        Children see throughput for 10 initial writers  =   14077.26 KB/sec
        Parent sees throughput for 10 initial writers   =   11850.11 KB/sec
        Min throughput per process                      =    1147.11 KB/sec
        Max throughput per process                      =    1650.14 KB/sec
        Avg throughput per process                      =    1407.73 KB/sec
        Min xfer                                        =  728832.00 KB

        Children see throughput for 10 rewriters        =    4563.71 KB/sec
        Parent sees throughput for 10 rewriters         =    4539.54 KB/sec
        Min throughput per process                      =     425.50 KB/sec
        Max throughput per process                      =     556.33 KB/sec
        Avg throughput per process                      =     456.37 KB/sec
        Min xfer                                        =  838144.00 KB

SLC4:

[root@lxxen0-u1 /]# iozone -M -c -e -w -i0 -r256k -s1g -t10 -F /tmp/d{1,2,3,4,5,6,7,8,9,0}
        Iozone: Performance Test of File I/O
                Version $Revision: 1.1 $
                Compiled for 32 bit mode.
                Build: linux

        Run began: Thu Nov 23 18:25:41 2006


        Machine = Linux lxxen0-u1 2.6.9-42.0.3.EL.cernxenU #1 SMP Tue Nov 21 10:54:28   Include close in write timing
        Include close in write timing
        Include fsync in write timing
        Setting no_unlink
        Record Size 256 KB
        File size set to 1048576 KB
        Command line used: iozone -M -c -e -w -i0 -r256k -s1g -t10 -F /tmp/d1 /tmp/d2 /tmp/d3 /tmp/d4 /tmp/d5 /tmp/d6 /tmp/d7 /tmp/d8 /tmp/d9 /tmp/d0
        Output is in Kbytes/sec
        Time Resolution = 0.000001 seconds.
        Processor cache size set to 1024 Kbytes.
        Processor cache line size set to 32 bytes.
        File stride size set to 17 * record size.
        Throughput test with 10 processes
        Each process writes a 1048576 Kbyte file in 256 Kbyte records

        Children see throughput for 10 initial writers  =   13562.90 KB/sec
        Parent sees throughput for 10 initial writers   =   10304.75 KB/sec
        Min throughput per process                      =     903.68 KB/sec
        Max throughput per process                      =    1857.85 KB/sec
        Avg throughput per process                      =    1356.29 KB/sec
        Min xfer                                        =  510464.00 KB

        Children see throughput for 10 rewriters        =    4905.64 KB/sec
        Parent sees throughput for 10 rewriters         =    4902.31 KB/sec
        Min throughput per process                      =     468.76 KB/sec
        Max throughput per process                      =     505.73 KB/sec
        Avg throughput per process                      =     490.56 KB/sec
        Min xfer                                        =  974848.00 KB

For comparison: same test run on the Xen host system gives figures below (as you can see .. it is not THAT performant):

[root@lxxen0 root]# iozone -M -c -e -w -i0 -r256k -s1g -t10 -F /tmp/d{1,2,3,4,5,6,7,8,9,0}
        Iozone: Performance Test of File I/O
                Version $Revision: 1.1 $
                Compiled for 32 bit mode.
                Build: linux

        Run began: Fri Nov 24 09:05:23 2006


        Machine = Linux lxxen0 2.6.16.29-xen_3.0.3.0 #1 SMP Wed Nov 22 10:20:52 CET 20  Include close in write timing
        Include close in write timing
        Include fsync in write timing
        Setting no_unlink
        Record Size 256 KB
        File size set to 1048576 KB
        Command line used: iozone -M -c -e -w -i0 -r256k -s1g -t10 -F /tmp/d1 /tmp/d2 /tmp/d3 /tmp/d4 /tmp/d5 /tmp/d6 /tmp/d7 /tmp/d8 /tmp/d9/tmp/d0
        Output is in Kbytes/sec
        Time Resolution = 0.000001 seconds.
        Processor cache size set to 1024 Kbytes.
        Processor cache line size set to 32 bytes.
        File stride size set to 17 * record size.
        Throughput test with 10 processes
        Each process writes a 1048576 Kbyte file in 256 Kbyte records

        Children see throughput for 10 initial writers  =   42421.14 KB/sec
        Parent sees throughput for 10 initial writers   =   35150.62 KB/sec
        Min throughput per process                      =    3105.44 KB/sec
        Max throughput per process                      =    5259.87 KB/sec
        Avg throughput per process                      =    4242.11 KB/sec
        Min xfer                                        =  628736.00 KB

        Children see throughput for 10 rewriters        =   39137.04 KB/sec
        Parent sees throughput for 10 rewriters         =   38896.64 KB/sec
        Min throughput per process                      =    3495.18 KB/sec
        Max throughput per process                      =    4104.54 KB/sec
        Avg throughput per process                      =    3913.70 KB/sec
        Min xfer                                        =  901120.00 KB