The cumulative time probably isn't that useful to detect changes in the
behavior of the application.
On 1/12/2021 12:30 PM, Chesnay Schepler wrote:
I mean the difference itself, not cumulative.
On 1/12/2021 12:08 PM, Manish G wrote:
Can you elaborate the second approach more?
Currently I am exposing the difference itself. OR do you mean the
cumulative difference?ie I maintain a member variable, say timeSoFar,
and update it with time consumed by each method call and then expose
it. Something like this:
timeSoFar += timeConsumedByCurrentInvocation
this.simpleGaug.setValue( timeSoFar );
On Tue, Jan 12, 2021 at 4:24 PM Chesnay Schepler <ches...@apache.org
<mailto:ches...@apache.org>> wrote:
That approach will generally not work for jobs that run for a
long time, because it will be nigh impossible for anomalies to
affect the average. You want to look into exponential moving
averages.
Alternatively, just expose the diff as an absolute value and
calculate the average in prometheus.
On 1/12/2021 11:50 AM, Manish G wrote:
OK, got it.
So I would need to accumulate the time value over the calls as
well as number of times it is called...and then calculate
average(accumulated time/ number of times called) and then set
calculated value into gauge as above.
On Tue, Jan 12, 2021 at 4:12 PM Chesnay Schepler
<ches...@apache.org <mailto:ches...@apache.org>> wrote:
A gauge just returns a value, and Flink exposes it as is. As
such you need to calculate the average over time yourself,
taking 2 time measurements (before and after the processing
of each).
On 1/12/2021 11:31 AM, Manish G wrote:
startTime is set at start of function:
long startTime = System.currentTimeMillis();
On Tue, Jan 12, 2021 at 3:59 PM Manish G
<manish.c.ghildi...@gmail.com
<mailto:manish.c.ghildi...@gmail.com>> wrote:
My code is:
|public class SimpleGauge<T> implements Gauge<T> {
private T mValue; @Override public T getValue() {
return mValue; } public void setValue(T value){ mValue
= value; } }|
And in flatmap function:
|float endTime = (System.currentTimeMillis() -
startTime) / 1000F; this.simplegauge.setValue(endTime); |
|So does it mean when flink calls my getValue function
to accumulate the value, and not to take it as snapshot? |
On Tue, Jan 12, 2021 at 3:53 PM Chesnay Schepler
<ches...@apache.org <mailto:ches...@apache.org>> wrote:
Sure, that might work. Be aware though that time
measurements are,
compared to the logic within a function, usually
rather expensive and
may impact performance.
On 1/12/2021 10:57 AM, Manish G wrote:
> Hi All,
>
> I have implemented a flatmap function and I want
to collect metrics
> for average time for this function which I plan
to monitor via prometheus.
>
> What would be good approach for it? I have added
a gauge to the
> method(extending Gauge interface from flink API).
Would it work for my
> needs?
>
>
