Mike,

To add some context, while NiFi will intelligently schedule processors to
execute, given HandleHTTPRequest's function as a listener, it is constantly
scheduled to run, checking for a request to handle.  I assume by number of
tasks, you mean the rolling count over the last 5 minutes.  As mentioned by
Andy, you can tamper this rate by increasing the run scheduld if the
handling of the HTTP requests with a slight latency is acceptable to you
and your needs.


On Thu, Jul 14, 2016 at 11:05 AM Andy LoPresto <[email protected]> wrote:

> Mike,
>
> You can adjust the processor properties for the HandleHTTPRequest
> processor in the scheduling tab.
>
> “Concurrent tasks” limits the number of threads this processor will use
> (default is 1)
> “Run schedule” determines the frequency that this processor will be run
> (default is ‘0 sec’ which means continuously)
>
> If you are only getting requests on a much slower schedule, you could
> reduce the run schedule to ~10 seconds and see if this is better for you. I
> have not encountered NiFi running at such high CPU percentage with that
> little data.
>
> As for the high number of tasks, that is definitely an anomaly.
> Configuration best practices [1] currently recommend increasing the limit
> to the 10k range, but 2.5M for a single processor is unusual. Can you
> inspect the logs (located in $NIFI_HOME/logs) to see if there are errors or
> more insight there?
>
> [1]
> https://nifi.apache.org/docs/nifi-docs/html/administration-guide.html#configuration-best-practices
>
>
>
> Andy LoPresto
> [email protected]
> *[email protected] <[email protected]>*
> PGP Fingerprint: 70EC B3E5 98A6 5A3F D3C4  BACE 3C6E F65B 2F7D EF69
>
> On Jul 14, 2016, at 10:36 AM, Mike Harding <[email protected]> wrote:
>
> ps - also noticed it seems to generate a lot of tasks, currently 2.5M
> compared to other processes in the pipeline which reports 10s of tasks.
>
> Mike
>
> On 14 July 2016 at 15:34, Mike Harding <[email protected]> wrote:
>
>>
>> Hi All,
>>
>> The node in my cluster running nifi crashed due to a CPU overload event.
>> After restarting I analysed the CPU consumption and found that nifi was the
>> issue. As you can see below it was running at 133% CPU:
>>
>> PID USER      PR  NI    VIRT    RES    SHR S  *%CPU* %MEM     TIME+
>> COMMAND
>>
>> 2031 nifi      20   0 3392960 990.7m  34124 S *113.4* 12.4   1179:47
>> java]
>>
>> I have only one data pipe line setup that is receiving data through a
>> HandleHTTPRequest processor and after playing around and turning other
>> processors off in the pipe it was only when I stopped this process that the
>> CPU dropped significantly to around 10% CPU.
>>
>> Its receiving around 67KB of data every 5 minutes from multiple requests
>> from a up stream web app.
>>
>> Has any one else seen this behaviour and or know whether there are ways
>> of managing the CPU usage of HandleHTTPRequest ?
>>
>> Thanks,
>>
>> Mike
>>
>
>
>

Reply via email to