VM's are slow after upgrading XEN Host to SLES 11 SP2
This document (7012823) is provided subject to the disclaimer at the end of this document.
SUSE Linux Enterprise Server 11 Service Pack 3
IP throughput appears to be considerably slower at times
To switch from threads back to tasklets for the netback pv driver:
"options netbk tasklets=1 bind=0"
to the modprobe.conf.local file.
A re-boot of the Host is required to instantiate the change.
Note: The bind option is to specify the processor you want them to run on. Default is 0 if left blank
To verify the change took effect, begin a file download on one of the vm's.
Then issue the following command:
ps aux | grep netback
If threads are still being used you will see the netback process in the output.
root 5219 0.0 0.0 0 0 ? S Jan19 0:00 [netback/0]
root 5220 0.0 0.0 0 0 ? S Jan19 0:00 [netback/1]
They will be absent if tasklets are in use.
Requires a XEN kernel dated 01/26/2013 or later on SLE11 SP2.
Previously, "tasklets" handled the IO.
Tasklets are the preferred method for VM-to-VM IP traffic.
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- Document ID:7012823
- Creation Date: 10-Jul-2013
- Modified Date:03-Mar-2020
- SUSE Linux Enterprise Server
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