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Posted to user@flink.apache.org by "Martin, Nick" <Ni...@ngc.com> on 2019/02/19 15:59:21 UTC
RE: EXT :Re: How to debug difference between Kinesis and Kafka
Yeah, that’s expected/known. Watermarks for the empty partition don’t advance, so the window in your window function never closes.
There’s a ticket open to fix it (https://issues.apache.org/jira/browse/FLINK-5479) for the kafka connector, but in general any time one parallel instance of a source function isn’t getting data you have to watch out for this.
From: Stephen Connolly [mailto:stephen.alan.connolly@gmail.com]
Sent: Tuesday, February 19, 2019 6:32 AM
To: user <us...@flink.apache.org>
Subject: EXT :Re: How to debug difference between Kinesis and Kafka
Hmmm my suspicions are now quite high. I created a file source that just replays the events straight then I get more results....
On Tue, 19 Feb 2019 at 11:50, Stephen Connolly <st...@gmail.com>> wrote:
Hmmm after expanding the dataset such that there was additional data that ended up on shard-0 (everything in my original dataset was coincidentally landing on shard-1) I am now getting output... should I expect this kind of behaviour if no data arrives at shard-0 ever?
On Tue, 19 Feb 2019 at 11:14, Stephen Connolly <st...@gmail.com>> wrote:
Hi, I’m having a strange situation and I would like to know where I should start trying to debug.
I have set up a configurable swap in source, with three implementations:
1. A mock implementation
2. A Kafka consumer implementation
3. A Kinesis consumer implementation
From injecting a log and no-op map function I can see that all three sources pass through the events correctly.
I then have a window based on event time stamps… and from inspecting the aggregation function I can see that the data is getting aggregated…, I’m using the `.aggregate(AggregateFunction.WindowFunction)` variant so that I can retrieve the key
Here’s the strange thing, I only change the source (and each source uses the same deserialization function) but:
* When I use either Kafka or my Mock source, the WindowFunction gets called as events pass the end of the window
* When I use the Kinesis source, however, the window function never gets called. I have even tried injecting events into kinesis with really high timestamps to flush the watermarks in my BoundedOutOfOrdernessTimestampExtractor... but nothing
I cannot see how this source switching could result in such a different behaviour:
Properties sourceProperties = new Properties();
ConsumerFactory sourceFactory;
String sourceName = configParams.getRequired("source");
switch (sourceName.toLowerCase(Locale.ENGLISH)) {
case "kinesis":
sourceFactory = FlinkKinesisConsumer::new;
copyOptionalArg(configParams, "aws-region", sourceProperties, AWSConfigConstants.AWS_REGION);
copyOptionalArg(configParams, "aws-endpoint", sourceProperties, AWSConfigConstants.AWS_ENDPOINT);
copyOptionalArg(configParams, "aws-access-key", sourceProperties, AWSConfigConstants.AWS_ACCESS_KEY_ID);
copyOptionalArg(configParams, "aws-secret-key", sourceProperties, AWSConfigConstants.AWS_SECRET_ACCESS_KEY);
copyOptionalArg(configParams, "aws-profile", sourceProperties, AWSConfigConstants.AWS_PROFILE_NAME);
break;
case "kafka":
sourceFactory = FlinkKafkaConsumer010::new;
copyRequiredArg(configParams, "bootstrap-server", sourceProperties, "bootstrap.servers");
copyOptionalArg(configParams, "group-id", sourceProperties, "group.id<http://group.id>");
break;
case "mock":
sourceFactory = MockSourceFunction::new;
break;
default:
throw new RuntimeException("Unknown source '" + sourceName + '\'');
}
// set up the streaming execution environment
final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
// poll watermark every second because using BoundedOutOfOrdernessTimestampExtractor
env.getConfig().setAutoWatermarkInterval(1000L);
env.enableCheckpointing(5000);
SplitStream<JsonNode> eventsByType = env.addSource(sourceFactory.create(
configParams.getRequired("topic"),
new ObjectNodeDeserializationSchema(),
sourceProperties
))
.returns(ObjectNode.class) // the use of ConsumerFactory erases the type info so add it back
.name("raw-events")
.assignTimestampsAndWatermarks(
new ObjectNodeBoundedOutOfOrdernessTimestampExtractor("timestamp", Time.seconds(5))
)
.split(new JsonNodeOutputSelector("eventType"));
...
eventsByType.select(...)
.keyBy(new JsonNodeStringKeySelector("_key"))
.window(TumblingEventOffsetPerKeyEventTimeWindows.of(Time.seconds(windowDuration),
(KeySelector<JsonNode, Time>) TasksMain::offsetPerMaster))
.trigger(EventTimeTrigger.create())
.aggregate(new CountsAggregator<>(), new KeyTagger<>()) // <==== The CountsAggregator is seeing the data
.print() // <==== HERE is where we get no output from Kinesis... but Kafka and my Mock are just fine!
________________________________
Notice: This e-mail is intended solely for use of the individual or entity to which it is addressed and may contain information that is proprietary, privileged and/or exempt from disclosure under applicable law. If the reader is not the intended recipient or agent responsible for delivering the message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. This communication may also contain data subject to U.S. export laws. If so, data subject to the International Traffic in Arms Regulation cannot be disseminated, distributed, transferred, or copied, whether incorporated or in its original form, to foreign nationals residing in the U.S. or abroad, absent the express prior approval of the U.S. Department of State. Data subject to the Export Administration Act may not be disseminated, distributed, transferred or copied contrary to U. S. Department of Commerce regulations. If you have received this communication in error, please notify the sender by reply e-mail and destroy the e-mail message and any physical copies made of the communication.
Thank you.
*********************
------------------------------------------------------------------------------
Notice: This e-mail is intended solely for use of the individual or entity to which it is addressed and may contain information that is proprietary, privileged and/or exempt from disclosure under applicable law. If the reader is not the intended recipient or agent responsible for delivering the message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. This communication may also contain data subject to U.S. export laws. If so, data subject to the International Traffic in Arms Regulation cannot be disseminated, distributed, transferred, or copied, whether incorporated or in its original form, to foreign nationals residing in the U.S. or abroad, absent the express prior approval of the U.S. Department of State. Data subject to the Export Administration Act may not be disseminated, distributed, transferred or copied contrary to U. S. Department of Commerce regulations. If you have received this communication in error, please notify the sender by reply e-mail and destroy the e-mail message and any physical copies made of the communication.
Thank you.
*********************
Re: EXT :Re: How to debug difference between Kinesis and Kafka
Posted by Dian Fu <di...@gmail.com>.
DataStream.assignTimestampsAndWatermarks will add a watermark generator operator after each source operator(if their parallelism is the same which is true for the code you showed) and so if one instance of the source operator has no data, the corresponding watermark generator operator cannot generate watermark.
Regards,
Dian
> 在 2019年2月20日，上午12:56，Stephen Connolly <st...@gmail.com> 写道：
>
> Though I am explicitly assigning watermarks with DataStream.assignTimestampsAndWatermarks and I see all the data flowing through that... so shouldn't that override the watermarks from the original source?
>
> On Tue, 19 Feb 2019 at 15:59, Martin, Nick <Nick.Martin@ngc.com <ma...@ngc.com>> wrote:
> Yeah, that’s expected/known. Watermarks for the empty partition don’t advance, so the window in your window function never closes.
>
>
>
> There’s a ticket open to fix it (https://issues.apache.org/jira/browse/FLINK-5479 <https://issues.apache.org/jira/browse/FLINK-5479>) for the kafka connector, but in general any time one parallel instance of a source function isn’t getting data you have to watch out for this.
>
>
>
> From: Stephen Connolly [mailto:stephen.alan.connolly@gmail.com <ma...@gmail.com>]
> Sent: Tuesday, February 19, 2019 6:32 AM
> To: user <user@flink.apache.org <ma...@flink.apache.org>>
> Subject: EXT :Re: How to debug difference between Kinesis and Kafka
>
>
>
> Hmmm my suspicions are now quite high. I created a file source that just replays the events straight then I get more results....
>
>
>
> On Tue, 19 Feb 2019 at 11:50, Stephen Connolly <stephen.alan.connolly@gmail.com <ma...@gmail.com>> wrote:
>
> Hmmm after expanding the dataset such that there was additional data that ended up on shard-0 (everything in my original dataset was coincidentally landing on shard-1) I am now getting output... should I expect this kind of behaviour if no data arrives at shard-0 ever?
>
>
>
> On Tue, 19 Feb 2019 at 11:14, Stephen Connolly <stephen.alan.connolly@gmail.com <ma...@gmail.com>> wrote:
>
> Hi, I’m having a strange situation and I would like to know where I should start trying to debug.
>
>
>
> I have set up a configurable swap in source, with three implementations:
>
>
>
> 1. A mock implementation
>
> 2. A Kafka consumer implementation
>
> 3. A Kinesis consumer implementation
>
>
>
> From injecting a log and no-op map function I can see that all three sources pass through the events correctly.
>
>
>
> I then have a window based on event time stamps… and from inspecting the aggregation function I can see that the data is getting aggregated…, I’m using the `.aggregate(AggregateFunction.WindowFunction)` variant so that I can retrieve the key
>
>
>
> Here’s the strange thing, I only change the source (and each source uses the same deserialization function) but:
>
>
>
> When I use either Kafka or my Mock source, the WindowFunction gets called as events pass the end of the window
> When I use the Kinesis source, however, the window function never gets called. I have even tried injecting events into kinesis with really high timestamps to flush the watermarks in my BoundedOutOfOrdernessTimestampExtractor... but nothing
> I cannot see how this source switching could result in such a different behaviour:
>
>
>
> Properties sourceProperties = new Properties();
>
> ConsumerFactory sourceFactory;
>
> String sourceName = configParams.getRequired("source");
>
> switch (sourceName.toLowerCase(Locale.ENGLISH)) {
>
> case "kinesis":
>
> sourceFactory = FlinkKinesisConsumer::new;
>
> copyOptionalArg(configParams, "aws-region", sourceProperties, AWSConfigConstants.AWS_REGION);
>
> copyOptionalArg(configParams, "aws-endpoint", sourceProperties, AWSConfigConstants.AWS_ENDPOINT);
>
> copyOptionalArg(configParams, "aws-access-key", sourceProperties, AWSConfigConstants.AWS_ACCESS_KEY_ID);
>
> copyOptionalArg(configParams, "aws-secret-key", sourceProperties, AWSConfigConstants.AWS_SECRET_ACCESS_KEY);
>
> copyOptionalArg(configParams, "aws-profile", sourceProperties, AWSConfigConstants.AWS_PROFILE_NAME);
>
> break;
>
> case "kafka":
>
> sourceFactory = FlinkKafkaConsumer010::new;
>
> copyRequiredArg(configParams, "bootstrap-server", sourceProperties, "bootstrap.servers");
>
> copyOptionalArg(configParams, "group-id", sourceProperties, "group.id <http://group.id/>");
>
> break;
>
> case "mock":
>
> sourceFactory = MockSourceFunction::new;
>
> break;
>
> default:
>
> throw new RuntimeException("Unknown source '" + sourceName + '\'');
>
> }
>
>
>
> // set up the streaming execution environment
>
> final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
>
>
>
> // poll watermark every second because using BoundedOutOfOrdernessTimestampExtractor
>
> env.getConfig().setAutoWatermarkInterval(1000L);
>
> env.enableCheckpointing(5000);
>
>
>
> SplitStream<JsonNode> eventsByType = env.addSource(sourceFactory.create(
>
> configParams.getRequired("topic"),
>
> new ObjectNodeDeserializationSchema(),
>
> sourceProperties
>
> ))
>
> .returns(ObjectNode.class) // the use of ConsumerFactory erases the type info so add it back
>
> .name("raw-events")
>
> .assignTimestampsAndWatermarks(
>
> new ObjectNodeBoundedOutOfOrdernessTimestampExtractor("timestamp", Time.seconds(5))
>
> )
>
> .split(new JsonNodeOutputSelector("eventType"));
>
> ...
>
> eventsByType.select(...)
>
> .keyBy(new JsonNodeStringKeySelector("_key"))
>
> .window(TumblingEventOffsetPerKeyEventTimeWindows.of(Time.seconds(windowDuration),
>
> (KeySelector<JsonNode, Time>) TasksMain::offsetPerMaster))
>
> .trigger(EventTimeTrigger.create())
>
> .aggregate(new CountsAggregator<>(), new KeyTagger<>()) // <==== The CountsAggregator is seeing the data
>
> .print() // <==== HERE is where we get no output from Kinesis... but Kafka and my Mock are just fine!
>
>
>
>
>
>
>
> Notice: This e-mail is intended solely for use of the individual or entity to which it is addressed and may contain information that is proprietary, privileged and/or exempt from disclosure under applicable law. If the reader is not the intended recipient or agent responsible for delivering the message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. This communication may also contain data subject to U.S. export laws. If so, data subject to the International Traffic in Arms Regulation cannot be disseminated, distributed, transferred, or copied, whether incorporated or in its original form, to foreign nationals residing in the U.S. or abroad, absent the express prior approval of the U.S. Department of State. Data subject to the Export Administration Act may not be disseminated, distributed, transferred or copied contrary to U. S. Department of Commerce regulations. If you have received this communication in error, please notify the sender by reply e-mail and destroy the e-mail message and any physical copies made of the communication.
> Thank you.
> *********************
>
>
> Notice: This e-mail is intended solely for use of the individual or entity to which it is addressed and may contain information that is proprietary, privileged and/or exempt from disclosure under applicable law. If the reader is not the intended recipient or agent responsible for delivering the message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. This communication may also contain data subject to U.S. export laws. If so, data subject to the International Traffic in Arms Regulation cannot be disseminated, distributed, transferred, or copied, whether incorporated or in its original form, to foreign nationals residing in the U.S. or abroad, absent the express prior approval of the U.S. Department of State. Data subject to the Export Administration Act may not be disseminated, distributed, transferred or copied contrary to U. S. Department of Commerce regulations. If you have received this communication in error, please notify the sender by reply e-mail and destroy the e-mail message and any physical copies made of the communication.
> Thank you.
> *********************
Re: EXT :Re: How to debug difference between Kinesis and Kafka
Posted by Stephen Connolly <st...@gmail.com>.
Though I am explicitly assigning watermarks with
DataStream.assignTimestampsAndWatermarks and I see all the data flowing
through that... so shouldn't that override the watermarks from the original
source?
On Tue, 19 Feb 2019 at 15:59, Martin, Nick <Ni...@ngc.com> wrote:
> Yeah, that’s expected/known. Watermarks for the empty partition don’t
> advance, so the window in your window function never closes.
>
>
>
> There’s a ticket open to fix it (
> https://issues.apache.org/jira/browse/FLINK-5479) for the kafka
> connector, but in general any time one parallel instance of a source
> function isn’t getting data you have to watch out for this.
>
>
>
> *From:* Stephen Connolly [mailto:stephen.alan.connolly@gmail.com]
> *Sent:* Tuesday, February 19, 2019 6:32 AM
> *To:* user <us...@flink.apache.org>
> *Subject:* EXT :Re: How to debug difference between Kinesis and Kafka
>
>
>
> Hmmm my suspicions are now quite high. I created a file source that just
> replays the events straight then I get more results....
>
>
>
> On Tue, 19 Feb 2019 at 11:50, Stephen Connolly <
> stephen.alan.connolly@gmail.com> wrote:
>
> Hmmm after expanding the dataset such that there was additional data that
> ended up on shard-0 (everything in my original dataset was coincidentally
> landing on shard-1) I am now getting output... should I expect this kind of
> behaviour if no data arrives at shard-0 ever?
>
>
>
> On Tue, 19 Feb 2019 at 11:14, Stephen Connolly <
> stephen.alan.connolly@gmail.com> wrote:
>
> Hi, I’m having a strange situation and I would like to know where I should
> start trying to debug.
>
>
>
> I have set up a configurable swap in source, with three implementations:
>
>
>
> 1. A mock implementation
>
> 2. A Kafka consumer implementation
>
> 3. A Kinesis consumer implementation
>
>
>
> From injecting a log and no-op map function I can see that all three
> sources pass through the events correctly.
>
>
>
> I then have a window based on event time stamps… and from inspecting the
> aggregation function I can see that the data is getting aggregated…, I’m
> using the `.aggregate(AggregateFunction.WindowFunction)` variant so that I
> can retrieve the key
>
>
>
> Here’s the strange thing, I only change the source (and each source uses
> the same deserialization function) but:
>
>
>
> - When I use either Kafka or my Mock source, the WindowFunction gets
> called as events pass the end of the window
> - When I use the Kinesis source, however, the window function never
> gets called. I have even tried injecting events into kinesis with really
> high timestamps to flush the watermarks in my
> BoundedOutOfOrdernessTimestampExtractor... but nothing
>
> I cannot see how this source switching could result in such a different
> behaviour:
>
>
>
> Properties sourceProperties = new Properties();
>
> ConsumerFactory sourceFactory;
>
> String sourceName = configParams.getRequired("source");
>
> switch (sourceName.toLowerCase(Locale.ENGLISH)) {
>
> case "kinesis":
>
> sourceFactory = FlinkKinesisConsumer::new;
>
> copyOptionalArg(configParams, "aws-region",
> sourceProperties, AWSConfigConstants.AWS_REGION);
>
> copyOptionalArg(configParams, "aws-endpoint",
> sourceProperties, AWSConfigConstants.AWS_ENDPOINT);
>
> copyOptionalArg(configParams, "aws-access-key",
> sourceProperties, AWSConfigConstants.AWS_ACCESS_KEY_ID);
>
> copyOptionalArg(configParams, "aws-secret-key",
> sourceProperties, AWSConfigConstants.AWS_SECRET_ACCESS_KEY);
>
> copyOptionalArg(configParams, "aws-profile",
> sourceProperties, AWSConfigConstants.AWS_PROFILE_NAME);
>
> break;
>
> case "kafka":
>
> sourceFactory = FlinkKafkaConsumer010::new;
>
> copyRequiredArg(configParams, "bootstrap-server",
> sourceProperties, "bootstrap.servers");
>
> copyOptionalArg(configParams, "group-id",
> sourceProperties, "group.id");
>
> break;
>
> case "mock":
>
> sourceFactory = MockSourceFunction::new;
>
> break;
>
> default:
>
> throw new RuntimeException("Unknown source '" + sourceName
> + '\'');
>
> }
>
>
>
> // set up the streaming execution environment
>
> final StreamExecutionEnvironment env =
> StreamExecutionEnvironment.getExecutionEnvironment();
>
>
>
> // poll watermark every second because using
> BoundedOutOfOrdernessTimestampExtractor
>
> env.getConfig().setAutoWatermarkInterval(1000L);
>
> env.enableCheckpointing(5000);
>
>
>
> SplitStream<JsonNode> eventsByType =
> env.addSource(sourceFactory.create(
>
> configParams.getRequired("topic"),
>
> new ObjectNodeDeserializationSchema(),
>
> sourceProperties
>
> ))
>
> .returns(ObjectNode.class) // the use of ConsumerFactory
> erases the type info so add it back
>
> .name("raw-events")
>
> .assignTimestampsAndWatermarks(
>
> new
> ObjectNodeBoundedOutOfOrdernessTimestampExtractor("timestamp",
> Time.seconds(5))
>
> )
>
> .split(new JsonNodeOutputSelector("eventType"));
>
> ...
>
> eventsByType.select(...)
>
> .keyBy(new JsonNodeStringKeySelector("_key"))
>
>
> .window(TumblingEventOffsetPerKeyEventTimeWindows.of(Time.seconds(windowDuration),
>
> (KeySelector<JsonNode, Time>)
> TasksMain::offsetPerMaster))
>
> .trigger(EventTimeTrigger.create())
>
> .aggregate(new CountsAggregator<>(), new KeyTagger<>()) //
> <==== The CountsAggregator is seeing the data
>
> .print() // <==== HERE is where we get no output from
> Kinesis... but Kafka and my Mock are just fine!
>
>
>
>
>
>
> ------------------------------
>
> Notice: This e-mail is intended solely for use of the individual or entity
> to which it is addressed and may contain information that is proprietary,
> privileged and/or exempt from disclosure under applicable law. If the
> reader is not the intended recipient or agent responsible for delivering
> the message to the intended recipient, you are hereby notified that any
> dissemination, distribution or copying of this communication is strictly
> prohibited. This communication may also contain data subject to U.S. export
> laws. If so, data subject to the International Traffic in Arms Regulation
> cannot be disseminated, distributed, transferred, or copied, whether
> incorporated or in its original form, to foreign nationals residing in the
> U.S. or abroad, absent the express prior approval of the U.S. Department of
> State. Data subject to the Export Administration Act may not be
> disseminated, distributed, transferred or copied contrary to U. S.
> Department of Commerce regulations. If you have received this communication
> in error, please notify the sender by reply e-mail and destroy the e-mail
> message and any physical copies made of the communication.
> Thank you.
> *********************
>
> ------------------------------
> Notice: This e-mail is intended solely for use of the individual or entity
> to which it is addressed and may contain information that is proprietary,
> privileged and/or exempt from disclosure under applicable law. If the
> reader is not the intended recipient or agent responsible for delivering
> the message to the intended recipient, you are hereby notified that any
> dissemination, distribution or copying of this communication is strictly
> prohibited. This communication may also contain data subject to U.S. export
> laws. If so, data subject to the International Traffic in Arms Regulation
> cannot be disseminated, distributed, transferred, or copied, whether
> incorporated or in its original form, to foreign nationals residing in the
> U.S. or abroad, absent the express prior approval of the U.S. Department of
> State. Data subject to the Export Administration Act may not be
> disseminated, distributed, transferred or copied contrary to U. S.
> Department of Commerce regulations. If you have received this communication
> in error, please notify the sender by reply e-mail and destroy the e-mail
> message and any physical copies made of the communication.
> Thank you.
> *********************
>