bad throughput performance on multiple systems: Re: Fwd: Re: Disappointing packets-per-second performance results on a Dell,PE R530

[John Jasen]

On 03/13/2017 01:03 PM, Navdeep Parhar wrote:

> On Sun, Mar 12, 2017 at 5:35 PM, John Jasen <jjasen at gmail.com> wrote:
>> UDP traffic. dmesg reports 16 txq, 8 rxq -- which is the default for
>> Chelsio.
>>
> I don't recall offhand, but UDP might be using 2-tuple hashing by
> default and that might affect the distribution of flows across queues.
> Are there senders generating IP fragments by any chance (that'll
> depend on the "send size" that your UDP application is using)?

No, they're not fragmenting.

> Have you tried limiting the adapter's rx ithreads to the CPU that the
> PCIe slot with the adapter is wired to?

Above and beyond the use of cpuset, you mean?