On Sun, Nov 22, 2009 at 10:44 PM, Mike Christie <micha...@cs.wisc.edu> wrote:
> Erez Zilber wrote:
>> On Thu, Nov 19, 2009 at 10:02 PM, Mike Christie <micha...@cs.wisc.edu> wrote:
>>> Ulrich Windl wrote:
>>>> On 19 Nov 2009 at 11:07, Erez Zilber wrote:
>>>>> On Thu, Nov 19, 2009 at 9:38 AM, Ulrich Windl
>>>>> <ulrich.wi...@rz.uni-regensburg.de> wrote:
>>>>>> Hi!
>>>>>> Wouldn't it be more obvious to calculate the average delay to a ping 
>>>>>> request?
>>>>>> (Possibly exponential average as for the system loads) (min and Max 
>>>>>> would be good
>>>>>> as well, but standard deviation probably requires use of the FPU, so 
>>>>>> that's not
>>>>>> possible in kernel modules (AFAIK)).
>>>>> It's in userspace, so (almost) everything is possible. It's nice to
>>>>> have counters, average delay etc, but I want to be able to know
>>>>> exactly when bad things almost happened (i.e. timeout almost expired).
>>>>> Counters/average delay will not help me.
>>>> I thought you want to tune the timeouts. So if properly tuned, the kernel 
>>>> will log
>>>> when when your measurements are unusual (i.e. timeout exceeded).
>>> I think that is what I wanted. I think Erez wants something a little
>>> different, right Erez?
>> I think that it would be nice if we had both:
>> 1. The average delay of a ping request.
>> 2. A list of ping requests that almost timed out with some helpful
>> info (when was the ping sent and how much time until we got a
>> response). With this information, you can understand and debug the
>> whole system: you can check your target and see what caused it to be
>> so slow on that specific time, you can see if your network was very
>> busy during that time etc.
> I think this sounds good to me.

Great. I will try to send a patch soon.



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