[other_os] VMWARE disk performance problems

Hi there,

I have a bunch of debian VMs on a pretty grunty ESX host,

These servers are just webservers running mysql and apache/php.

The problem I have is one server always seems to get all the resources in regards to disk i/o.

To be fair it is quite a heavy web application. (4 years of development and still going), For example host01 is the machine that is having long page loads etc.
mailinator is essentially the same as host01, but its disk I/O is fine.

Both machines have the latest version of VMware tools on them. And they use the same physical datastore.

Here are the test results.

daryl@mailinator:~$ sudo hdparm -t /dev/sda1
[sudo] password for daryl:
/dev/sda1:
Timing buffered disk reads: 390 MB in 3.01 seconds = 129.60 MB/sec

daryl@host01:~$ sudo hdparm -t /dev/sda1
[sudo] password for daryl:

/dev/sda1:
Timing buffered disk reads: 34 MB in 4.13 seconds = 8.23 MB/sec

For a web server this is pretty bad, it only really needs about 40MB/sec to be sufficent

Both of these machines spec is:
2vCPU
4096MB Ram

The only thing in VMware that i can find different is the guest os on the slow machine (host01) says Other 2.6.x Linux (64-bit)

The faster machine (mailinator) says Other (32bit) which is wrong as well, since both of these machines are debian squeeze 64bit. So any suggestions on what I can do??

They both got the same amount of shares for disk IO and the same priority as far as VSPHERE is concerned.