That said, is there a way to get a dump of all metrics exposed by TM. I was
searching for it and I bet we could get it for ServieMonitor on k8s (
scrape ) but am missing a way to het a TM and dump all metrics that are
pushed.
Thanks and regards.
On Tue, Mar 23, 2021 at 5:56 PM Vishal Santoshi <vishal.santo...@gmail.com>
wrote:
> I guess there is a bigger issue here. We dropped the property to 500. We
> also realized that this failure happened on a TM that had one specific job
> running on it. What was good ( but surprising ) that the exception was the
> more protocol specific 413 ( as in the chunk is greater then some size
> limit DD has on a request.
>
> Failed to send request to Datadog (response was Response{protocol=h2,
> code=413, message=, url=
> https://app.datadoghq.com/api/v1/series?api_key=**********}
> <https://app.datadoghq.com/api/v1/series?api_key=0ffa36e48f5042465635b5843fa3f2a6%7D>
> )
>
> which implies that the Socket timeout was masking this issue. The 2000 was
> just a huge payload that DD was unable to parse in time ( or was slow to
> upload etc ). Now we could go lower but that makes less sense. We could
> play with
> https://ci.apache.org/projects/flink/flink-docs-stable/ops/metrics.html#system-scope
> to reduce the size of the tags ( or keys ).
>
>
>
>
>
>
>
>
>
> On Tue, Mar 23, 2021 at 11:33 AM Vishal Santoshi <
> vishal.santo...@gmail.com> wrote:
>
>> If we look at this
>> <https://github.com/apache/flink/blob/97bfd049951f8d52a2e0aed14265074c4255ead0/flink-metrics/flink-metrics-datadog/src/main/java/org/apache/flink/metrics/datadog/DatadogHttpReporter.java#L159>
>> code , the metrics are divided into chunks up-to a max size. and enqueued
>> <https://github.com/apache/flink/blob/97bfd049951f8d52a2e0aed14265074c4255ead0/flink-metrics/flink-metrics-datadog/src/main/java/org/apache/flink/metrics/datadog/DatadogHttpClient.java#L110>.
>> The Request
>> <https://github.com/apache/flink/blob/97bfd049951f8d52a2e0aed14265074c4255ead0/flink-metrics/flink-metrics-datadog/src/main/java/org/apache/flink/metrics/datadog/DatadogHttpClient.java#L75>
>> has a 3 second read/connect/write timeout which IMHO should have been
>> configurable ( or is it ) . While the number metrics ( all metrics )
>> exposed by flink cluster is pretty high ( and the names of the metrics
>> along with tags ) , it may make sense to limit the number of metrics in a
>> single chunk ( to ultimately limit the size of a single chunk ). There is
>> this configuration which allows for reducing the metrics in a single chunk
>>
>> metrics.reporter.dghttp.maxMetricsPerRequest: 2000
>>
>> We could decrease this to 1500 ( 1500 is pretty, not based on any
>> empirical reasoning ) and see if that stabilizes the dispatch. It is
>> inevitable that the number of requests will grow and we may hit the
>> throttle but then we know the exception rather than the timeouts that are
>> generally less intuitive.
>>
>> Any thoughts?
>>
>>
>>
>> On Mon, Mar 22, 2021 at 10:37 AM Arvid Heise <ar...@apache.org> wrote:
>>
>>> Hi Vishal,
>>>
>>> I have no experience in the Flink+DataDog setup but worked a bit with
>>> DataDog before.
>>> I'd agree that the timeout does not seem like a rate limit. It would
>>> also be odd that the other TMs with a similar rate still pass. So I'd
>>> suspect n/w issues.
>>> Can you log into the TM's machine and try out manually how the system
>>> behaves?
>>>
>>> On Sat, Mar 20, 2021 at 1:44 PM Vishal Santoshi <
>>> vishal.santo...@gmail.com> wrote:
>>>
>>>> Hello folks,
>>>> This is quite strange. We see a TM stop reporting
>>>> metrics to DataDog .The logs from that specific TM for every DataDog
>>>> dispatch time out with* java.net.SocketTimeoutException: timeout *and
>>>> that seems to repeat over every dispatch to DataDog. It seems it is on a 10
>>>> seconds cadence per container. The TM remains humming, so does not seem to
>>>> be under memory/CPU distress. And the exception is *not* transient. It
>>>> just stops dead and from there on timeout.
>>>>
>>>> Looking at SLA provided by DataDog any throttling exception should
>>>> pretty much not be a SocketTimeOut, till of course the reporting the
>>>> specific issue is off. This thus appears very much a n/w issue which
>>>> appears weird as other TMs with the same n/w just hum along, sending their
>>>> metrics successfully. The other issue could be just the amount of metrics
>>>> and the current volume for the TM is prohibitive. That said the exception
>>>> is still not helpful.
>>>>
>>>> Any ideas from folks who have used DataDog reporter with Flink. I guess
>>>> even best practices may be a sufficient beginning.
>>>>
>>>> Regards.
>>>>
>>>>
