Clustered Nifi running erratically,the issue often appear - apache-nifi

java.net.SocketTimeoutException: Read timed out
3 NODE,Nifi-1.10.0,ZK-3.6.5
i reset the relevant setting to make Nifi to respond in given time as following.But this ways can't work!?
nifi.cluster.node.connection.timeout=120 sec
nifi.cluster.node.read.timeout=120 sec
nifi.zookeeper.connect.timeout=30 secs
nifi.zookeeper.session.timeout=30 secs
nifi.zookeeper.connect.timeout=30 secs
nifi.zookeeper.session.timeout=30 secs
nifi.cluster.load.balance.comms.timeout=30 sec
UPDATED:
While enter NIFI UI,Nifi can't running.There are only an app in this VM.
3 Node has same spec and configuration
java.arg.2=-Xms4g
java.arg.3=-Xmx4g
NIFI-APP.LOG
2020-06-03 08:54:27,845 WARN [Curator-ConnectionStateManager-0] o.a.c.f.state.ConnectionStateManager Session timeout has elapsed while SUSPENDED. Injecting a session expiration. Elapsed ms: 32546. Adjusted session timeout ms: 30000
ZK-LOG
2020-06-02 18:12:45,232 [myid:1] - WARN [NIOWorkerThread-5:NIOServerCnxn#366] - Unable to read additional data from client sessionid 0x1014019b26f0005, likely client has closed socket

#Kong a few things to consider:
Set your min max at 4g and 8g, work up to 60-70% of the total ram of the node. Restart Nifi often to reset ram stolen from memory leaks. Restart all before adjusting for performance.
Check your max thread tuning. This needs to be based on the number of cores you have. Default settings will not make full use of the node cores.
Adjust Garbage Collection - there are quite a few posts around with info on what to do here.
Inspect flow for bad concurrency or schedule settings. A processor on the wrong schedule (0 sec for example), or with large concurrency can create instability.
I suspect you have a small combination of settings to adjust and you should see the stability you are looking for.

I suppose that the memory of JVM is too much,so that VM isn't enough for performance to make the Zookeeper work.
Tune JVM to 2G,the Nifi can work successfully.

Related

Kafka elasticsearch connector - 'Flush timeout expired with unflushed records:'

I have a strange problem with kafka -> elasticsearch connector. First time when I started it all was great, I received a new data in elasticsearch and checked it through kibana dashboard, but when I produced new data in to kafka using the same producer application and tried to start connector one more time, I didn't get any new data in elasticsearch.
Now I'm getting such errors:
[2018-02-04 21:38:04,987] ERROR WorkerSinkTask{id=log-platform-elastic-0} Commit of offsets threw an unexpected exception for sequence number 14: null (org.apache.kafka.connect.runtime.WorkerSinkTask:233)
org.apache.kafka.connect.errors.ConnectException: Flush timeout expired with unflushed records: 15805
I'm using next command to run connector:
/usr/bin/connect-standalone /etc/schema-registry/connect-avro-standalone.properties log-platform-elastic.properties
connect-avro-standalone.properties:
bootstrap.servers=kafka-0.kafka-hs:9093,kafka-1.kafka-hs:9093,kafka-2.kafka-hs:9093
key.converter=io.confluent.connect.avro.AvroConverter
key.converter.schema.registry.url=http://localhost:8081
value.converter=io.confluent.connect.avro.AvroConverter
value.converter.schema.registry.url=http://localhost:8081
internal.key.converter=org.apache.kafka.connect.json.JsonConverter
internal.value.converter=org.apache.kafka.connect.json.JsonConverter
internal.key.converter.schemas.enable=false
internal.value.converter.schemas.enable=false
offset.storage.file.filename=/tmp/connect.offsets
# producer.interceptor.classes=io.confluent.monitoring.clients.interceptor.MonitoringProducerInterceptor
# consumer.interceptor.classes=io.confluent.monitoring.clients.interceptor.MonitoringConsumerInterceptor
#rest.host.name=
rest.port=8084
#rest.advertised.host.name=
#rest.advertised.port=
plugin.path=/usr/share/java
and log-platform-elastic.properties:
name=log-platform-elastic
key.converter=org.apache.kafka.connect.storage.StringConverter
connector.class=io.confluent.connect.elasticsearch.ElasticsearchSinkConnector
tasks.max=1
topics=member_sync_log, order_history_sync_log # ... and many others
key.ignore=true
connection.url=http://elasticsearch:9200
type.name=log
I checked connection to kafka brokers, elasticsearch and schema-registry(schema-registry and connector are on the same host at this moment) and all is fine. Kafka brokers are running on port 9093 and I'm able to read data from topics using kafka-avro-console-consumer.
I'll be gratefull for any help on this!
Just update flush.timeout.ms to bigger than 10000 (10 seconds which is the default)
According to documentation:
flush.timeout.ms
The timeout in milliseconds to use for periodic
flushing, and when waiting for buffer space to be made available by
completed requests as records are added. If this timeout is exceeded
the task will fail.
Type: long Default: 10000 Importance: low
See documentation
We can optimized Elastic search configuration to solve issue. Please refer below link for configuration parameter
https://docs.confluent.io/current/connect/kafka-connect-elasticsearch/configuration_options.html
Below are key parameter which can control message rate flow to eventually help to solve issue:
flush.timeout.ms: Increase might help to give more breath on flush time
The timeout in milliseconds to use for periodic flushing, and when
waiting for buffer space to be made available by completed requests as
records are added. If this timeout is exceeded the task will fail.
max.buffered.records: Try reducing buffer record limit
The maximum number of records each task will buffer before blocking
acceptance of more records. This config can be used to limit the
memory usage for each task
batch.size: Try reducing batch size
The number of records to process as a batch when writing to
Elasticsearch
tasks.max: Number of parallel thread(consumer instance) Reduce or Increase. This will control Elastic Search if bandwidth not able to handle reduce task may help.
It worked my issue by tuning above parameters

Spark job just hangs with large data

I am trying to query from s3 (15 days of data). I tried querying them separately (each day) it works fine. It works fine for 14 days as well. But when I query 15 days the job keeps running forever (hangs) and the task # is not updating.
My settings :
I am using 51 node cluster r3.4x large with dynamic allocation and maximum resource turned on.
All I am doing is =
val startTime="2017-11-21T08:00:00Z"
val endTime="2017-12-05T08:00:00Z"
val start = DateUtils.getLocalTimeStamp( startTime )
val end = DateUtils.getLocalTimeStamp( endTime )
val days: Int = Days.daysBetween( start, end ).getDays
val files: Seq[String] = (0 to days)
.map( start.plusDays )
.map( d => s"$input_path${DateTimeFormat.forPattern( "yyyy/MM/dd" ).print( d )}/*/*" )
sqlSession.sparkContext.textFile( files.mkString( "," ) ).count
When I run the same with 14 days, I got 197337380 (count) and I ran the 15th day separately and got 27676788. But when I query 15 days total the job hangs
Update :
The job works fine with :
var df = sqlSession.createDataFrame(sc.emptyRDD[Row], schema)
for(n <- files ){
val tempDF = sqlSession.read.schema( schema ).json(n)
df = df(tempDF)
}
df.count
But can some one explain why it works now but not before ?
UPDATE : After setting mapreduce.input.fileinputformat.split.minsize to 256 GB it works fine now.
Dynamic allocation and maximize resource allocation are both different settings, one would be disabled when other is active. With Maximize resource allocation in EMR, 1 executor per node is launched, and it allocates all the cores and memory to that executor.
I would recommend taking a different route. You seem to have a pretty big cluster with 51 nodes, not sure if it is even required. However, follow this rule of thumb to begin with, and you will get a hang of how to tune these configurations.
Cluster memory - minimum of 2X the data you are dealing with.
Now assuming 51 nodes is what you require, try below:
r3.4x has 16 CPUs - so you can put all of them to use by leaving one for the OS and other processes.
Set your number of executors to 150 - this will allocate 3 executors per node.
Set number of cores per executor to 5 (3 executors per node)
Set your executor memory to roughly total host memory/3 = 35G
You got to control the parallelism (default partitions), set this to number of total cores you have ~ 800
Adjust shuffle partitions - make this twice of number of cores - 1600
Above configurations have been working like a charm for me. You can monitor the resource utilization on Spark UI.
Also, in your yarn config /etc/hadoop/conf/capacity-scheduler.xml file, set yarn.scheduler.capacity.resource-calculator to org.apache.hadoop.yarn.util.resource.DominantResourceCalculator - which will allow Spark to really go full throttle with those CPUs. Restart yarn service after change.
You should be increasing the executor memory and # executors, If the data is huge try increasing the Driver memory.
My suggestion is to not use the dynamic resource allocation and let it run and see if it still hangs or not (Please note that spark job can consume entire cluster resources and make other applications starve for resources try this approach when no jobs are running). if it doesn't hang that means you should play with the resource allocation, then start hardcoding the resources and keep increasing resources so that you can find the best resource allocation you can possibly use.
Below links can help you understand the resource allocation and optimization of resources.
http://site.clairvoyantsoft.com/understanding-resource-allocation-configurations-spark-application/
https://community.hortonworks.com/articles/42803/spark-on-yarn-executor-resource-allocation-optimiz.html

Socket Exception while running load test with Self Provisioned test rig

I am getting the Socket Exception while running load test on self-provisioned test rig.
I am trigger those load tests in agent machine(self-provisioned test rig) from my local machine.
Note : For first 2 to 3 minutes test iterations are passing , after that we are getting the Socket Exception.
Below is the error message :
A connection attempt failed because the connected party did not
properly respond after a period of time, or established connection
failed because connected host has failed to respond.
Below are the stack trace details :
at System.Net.Sockets.Socket.EndConnect(IAsyncResult asyncResult) at
System.Net.ServicePoint.ConnectSocketInternal(Boolean connectFailure,
Socket s4, Socket s6, Socket& socket, IPAddress& address,
ConnectSocketState state, IAsyncResult asyncResult, Exception&
exception)
Run Time - 20min
Sample rate - 10sec
warm up duration 10sec
number of agents used - 2
Load pattern :
initial load - 10user
max user count - 300
step duration - 10sec
step user count - 10
Although, by Changing above values I am still getting the exception in the same way.
I am using Visual studio 2015 enterprise.
The question states: start with 10 users, every 10 seconds add 10 users to a maximum of 300. Thus after 29 increments there will be 300 users and that will take 29*10 seconds which is 4m50s. The test will thus (attempt to) run with the maximum load of 300 users for the remaining 15m10s.
Given that all tests pass for the first 2 or 3 minutes plus the the error message, that suggests that you are overloading some part of the network. It might be the agents, it might be the servers or it might be on the connections between them. Some network components have a maximum number of active connections and the 300 users might be too many.
Increasing the load so rapidly means you do not clearly know what the limiting value. The sampling rate (at 10 seconds) seems high. At each sampling interval a lot of data is transferred (i.e. the sample data) and that can swamp parts of the network. You should look at the network counters for the agents and controller, also the servers if available.
I recommend changing the load test steps to add 10 users every 30 seconds, so it takes about 15 minutes to reach 300 users. It may also be worth reducing the sample rate to every 20 seconds.

java.net.SocketException:connection reset in JMeter [duplicate]

I have the next test plan in JMeter:
on the screenshot you can see the settings for the 1st ThreadGroup, wich has 50% of common amout of request in test plan (in each Thread Group are 10 different subrequests placed).
So, +1 request per second is added in average using these settings.
Then I ran this test and saw this picture (Error % column):
I save errors in file and all these errors have the same text:
<sample t="30129" lt="0" ts="1356710138314" s="false" lb="WebService(SOAP) Request 1" rc="000" rm="**Connection reset**" tn="jp#gc - Stepping Thread Group1 3-247" dt="text" by="0"/>
Server's cpu screenshot:
and for database:
After the errors have appeared my comp started work slowly and slowly (although the errors stopped to appear further)...
And in the same time the server's cpu progressively dropped to 0.
Could you tell me, please,
What is the reason of this error?
Have I reached the server timeout? (Because Max is more than 30s in the table).
UPD. I have rerun test with next settings: 1000 users per 02:46:40 (+1 Thread Group per 10 second and 10 requests inside each new Thread in the Loop).
I.e. I have reduced the time of test and total Thread Groups by 2 times, but save intensivity of Thead's adding.
The results are the same (including cpu usage on the server).
I've received the error «Connection reset» after 990 thread started. There are screenshots:
Any idea?
First, WebService(SOAP) Request is not the best way to test Webservices in JMeter, it will be deprecated in upcoming 2.9 version.
HTTP Sampler is the one to choose as it performs much better.
Second, Connection Reset means your server has cut connection. It could be coming from the CPU which seems high but it's not sure.
If what you call "my comp" is the computer hosting JMeter started working slowly then your JMeter instance is overwhelmed by the number of threads (2003 or more?) you've configured. It can come from a lot of factors, read this:
http://www.dzone.com/links/see_how_to_make_jmeter_run_thousands_of_threads_w.html

MongoDB-Java performance with rebuilt Sync driver vs Async

I have been testing MongoDB 2.6.7 for the last couple of months using YCSB 0.1.4. I have captured good data comparing SSD to HDD and am producing engineering reports.
After my testing was completed, I wanted to explore the allanbank async driver. When I got it up and running (I am not a developer, so it was a challenge for me), I first wanted to try the rebuilt sync driver. I found performance improvements of 30-100%, depending on the workload, and was very happy with it.
Next, I tried the async driver. I was not able to see much difference between it and my results with the native driver.
The command I'm running is:
./bin/ycsb run mongodb -s -P workloads/workloadb -p mongodb.url=mongodb://192.168.0.13:27017/ycsb -p mongodb.writeConcern=strict -threads 96
Over the course of my testing (mostly with the native driver), I have experimented with more and less threads than 96; turned on "noatime"; tried both xfs and ext4; disabled hyperthreading; disabled half my 12 cores; put the journal on a different drive; changed sync from 60 seconds to 1 second; and checked the network bandwidth between the client and server to ensure its not oversubscribed (10GbE).
Any feedback or suggestions welcome.
The Async move exceeded my expectations. My experience is with the Python Sync (pymongo) and Async driver (motor) and the Async driver achieved greater than 10x the throughput. further, motor is still using pymongo under the hoods but adds the async ability. that could easily be the case with your allanbank driver.
Often the dramatic changes come from threading policies and OS configurations.
Async needn't and shouldn't use any more threads than cores on the VM or machine. For example, if you're server code is spawning a new thread per incoming conn -- then all bets are off. start by looking at the way the driver is being utilized. A 4 core machine uses <= 4 incoming threads.
On the OS level, you may have to fine-tune parameters like net.core.somaxconn, net.core.netdev_max_backlog, sys.fs.file_max, /etc/security/limits.conf nofile and the best place to start is looking at nginx related performance guides including this one. nginx is the server that spearheaded or at least caught the attention of many linux sysadmin enthusiasts. Contrary to popular lore one should reduce your keepalive timeout opposed to lengthen it. The default keep-alive timeout is some absurd (4 hours) number of seconds. you might want to cut the cord in 1 minute. basically, think a short sweet relationship with your clients connections.
Bear in mind that Mongo is not Async so you can use a Mongo driver pool. nevertheless, don't let the driver get stalled on slow queries. cut it off in 5 to 10 seconds using the following equivalents in Java. I'm just cutting and pasting here with no recommendations.
# Specifies a time limit for a query operation. If the specified time is exceeded, the operation will be aborted and ExecutionTimeout is raised. If max_time_ms is None no limit is applied.
# Raises TypeError if max_time_ms is not an integer or None. Raises InvalidOperation if this Cursor has already been used.
CONN_MAX_TIME_MS = None
# socketTimeoutMS: (integer) How long (in milliseconds) a send or receive on a socket can take before timing out. Defaults to None (no timeout).
CLIENT_SOCKET_TIMEOUT_MS=None
# connectTimeoutMS: (integer) How long (in milliseconds) a connection can take to be opened before timing out. Defaults to 20000.
CLIENT_CONNECT_TIMEOUT_MS=20000
# waitQueueTimeoutMS: (integer) How long (in milliseconds) a thread will wait for a socket from the pool if the pool has no free sockets. Defaults to None (no timeout).
CLIENT_WAIT_QUEUE_TIMEOUT_MS=None
# waitQueueMultiple: (integer) Multiplied by max_pool_size to give the number of threads allowed to wait for a socket at one time. Defaults to None (no waiters).
CLIENT_WAIT_QUEUE_MULTIPLY=None
Hopefully you will have the same success. I was ready to bail on Python prior to async

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