| |
|
 |
|
 |
|
|
|
| |
|
|
xen-users
RE: [Xen-users] Poor performance running apache under xen
This sounds similar to a problem I had. For my system setting
"EnableSendfile off" in the apache config fixed things for me.
-Adam
| -----Original Message-----
| From: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
| [mailto:xen-users-bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of
| Richard@xxxxxxxxxxxxxxx
| Sent: Wednesday, July 26, 2006 10:12 PM
| To: xen-users@xxxxxxxxxxxxxxxxxxx
| Subject: [Xen-users] Poor performance running apache under xen
|
| We've been seeing a fairly significant slow down of a
| fairly large, in
| house java application based on apache tomcat, when running
| under xen.
| In order to gain some insight into this I've run similar tests using
| Apache2 and ApacheBench and we are seeing almost exactly
| the same slow
| down of about 24% (23.8% for our application and 23.5% for apache).
|
| The test consisted of sending one million reqests to the
| web server and
| was run from a different machine over gigbit ethernet.
| During the tests
| the driving machine did not go over 15% cpu load and the 1
| min load avg
| did not go over 2. The machine under test had nothing else
| running. The
| results given are for the second of two runs after a reboot. The cpu
| usage is the average over the entire run obtained from sar
| with a four
| second average (sar 4 0). The cpu figure is of the machine
| running the
| test. The /lib/tls directory was removed.
|
| The tests where carried out using the following versions of
| software:
|
| * Ubuntu 5.10 (Breezy Badger) using Debian 32bit kernels
| * Xen 3.0.2
| * Apache 2.0.54 using both the mpm-prefork (multi-process
| worker) and the
| mpm-worker (hybrid multi-threaded multi-process worker)
| * ApacheBench 2.0.41-dev
|
| The different kernel configurations are:
|
| Stock kernel: 2.6.16-2-686-smp #1 SMP
| dom0 kernel: 2.6.16-1-xen-686 #1 SMP
| domU kernel: 2.6.16-1-xen-686 #1 SMP
|
| The throughput is:
|
| Kernel throughput % cpu (user + system)
| stock kernel (prefork): 5019.42 24.31
| stock kernel (worker): 4800.20 30.37
| dom0 kernel (prefork): 5029.60 22.37
| dom0 kernel (worker): 4843.59 29.97
| domU kernel (prefork): 3726.44 38.80
| domU kernel (worker): 3704.95 41.32
|
| The reason I tested both the mpm-prefork and mpm-worker is
| test to see
| if the threading concurrency model made a big difference --
| it didn't!
|
| Can anyone shed any light on these results? Is this the normal
| performance that is to be expected from this type of application?
|
| I've put all the results (ApacheBench results and the sar
| outputs) on
| http://twosecondmemory.org/xen-performance/
|
| rgh
|
|
| _______________________________________________
| Xen-users mailing list
| Xen-users@xxxxxxxxxxxxxxxxxxx
| http://lists.xensource.com/xen-users
|
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
|
|
|
| |
|
Home