Erez Zilber wrote:
> On Thu, Nov 19, 2009 at 10:02 PM, Mike Christie <> 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
>>>> <> 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.


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