| |
|
 |
|
 |
|
|
|
| |
|
|
xen-users
Re: [Xen-users] Re: Windows Disk performance
Christian Tramnitz wrote:
Ruslan Sivak schrieb:
I've been getting disappointing results on IO reads when using
windows guests. I'm getting usually around 70MB/s reads using
hdtune. When installing James' PV drivers, the speed drops to about
20MB/s.
The host system is getting around 350MB/s reads. I'm wondering if
there is such a significant slowdown, or if my tests are somehow
flawed. The 70MB/s persisted throughout my VM testing, whether I was
using Xen, XenSource or VMWare Server.
So my questions are:
a. Is there a bottleneck somewhere which basically caps the windows
disk performance?
b. Is my testing methodology flawed. Is there a better windows tool
that will measure performance? What about Linux tool? I'm currently
using hdparm -t
Russ
Hi Russ,
first of all let's clarify:
- Is this Mb as in "Megabits per second" or MB as in "Megabytes per
second"? You stated both in your original post in the 0.95 driver
thread, so I want to make sure...
I would think MegaBytes per second.
- Did you use the same measurement/tools in all 3 scenarios (dom0,
domU/stock, domU/gplpv)? If yes how exactly? (I'm not aware of hdtune
for linux, so you most probably ran something else to get dom0
performance)
dom0 i used htdune -t /dev/sda
domU/stock and domU/gplpv I used hdtune.
I think the answer to #2 will explain the big difference between dom0
and domU performance (taking into account a bit of a general overhead).
When it comes to PV driver's performance this is an interesting topic.
I've seen posts giving the opposite (not exact numbers but direction)
result, so it would be interesting to find out what causes this.
James mentioned something about something not being aligned properly.
This might fix it, as on my dom0, I went from about 150mb/s with hdparm
to 350 mb/s after adjusting some parameters as per the 3ware site.
Russ
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
|
|
|
| |
|
Home