Troubleshooting for performance issues
|Symptom||High volume traffic through an emulated OSA-Express® ethernet adapter on ZVDT suffers poor throughput.|
If newer Linux® kernels are installed, you might experience a drastic slowdown of OSA performance, This slowdown is immediately obvious and is due to Linux attempting to offload various functions into the adapter, which is not acceptable to the current awsOSA implementation. One or more of the following commands, intended to disable the Linux offloading of IP functions, might improve the situation:
You might need to experiment with these commands.
These commands must be entered after each Linux boot. If
a script is used to start ZVDT, such as the
Effective combinations of these options differ with various Linux levels and with various NIC adapters. This problem was first noticed with Linux kernel level 184.108.40.206
If frames larger than expected are used, an excessive number of frames might be dropped (causing
a re-transmission). This may not be noticed unless careful measurements or comparisons are made.
This problem might be resolved by including the
|Symptom||ZVDT performs slowly. CPUs reach 100% utilization.|
|Problem Determination||Verify that you are meeting the minimum requirements for both the hardware and the software. See Hardware and software requirements.|