I set up a spark-yarn cluster environment, and try spark-SQL with spark-shell:
spark-shell --master yarn --deploy-mode client --conf spark.yarn.archive=hdfs://hadoop_273_namenode_ip:namenode_port/spark-archive.zip
One thing to mention is the Spark is in Windows 7. After spark-shell starts up successfully, I execute the commands as below:
scala> val sqlContext = new org.apache.spark.sql.SQLContext(sc)
scala> val df_mysql_address = sqlContext.read.format("jdbc").option("url", "jdbc:mysql://mysql_db_ip/db").option("driver", "com.mysql.jdbc.Driver").option("dbtable", "ADDRESS").option("user", "root").option("password", "root").load()
scala> df_mysql_address.show
scala> df_mysql_address.write.format("parquet").saveAsTable("address_local")
"show" command returns result-set correctly, but the "saveAsTable" ends in failure. The error message says:
java.io.IOException: Mkdirs failed to create file:/C:/jshen.workspace/programs/spark-2.2.0-bin-hadoop2.7/spark-warehouse/address_local/_temporary/0/_temporary/attempt_20171018104423_0001_m_000000_0 (exists=false, cwd=file:/tmp/hadoop/nm-local-dir/usercache/hduser/appcache/application_1508319604173_0005/container_1508319604173_0005_01_000003)
I expect and guess the table is to be saved in the hadoop cluster, but you can see that the dir (C:/jshen.workspace/programs/spark-2.2.0-bin-hadoop2.7/spark-warehouse) is the folder in my Windows 7, not in hdfs, not even in the hadoop ubuntu machine.
How could I do? Please advise, thanks.
The way to get rid of the problem is to provide "path" option prior to "save" operation as shown below:
scala> df_mysql_address.write.option("path", "/spark-warehouse").format("parquet").saveAsTable("address_local")
Thanks #philantrovert.
Related
I want to integrate Spark GraphX with Neo4j using 1
I tried to follow the steps in 2 but it doesn't work.
What should I do exactly with the neo4j-connector-apache-spark_2.12-4.0.0.jar file ? I put it in the jar files in the Spark folder.
in bash I write:
C:>Spark\spark-3.1.1-bin-hadoop2.7\bin\spark-shell --jars neo4j-connector-apache-spark_2.12-4.0.0.jar
Any suggestions please?
Update no. 1
I tried this C:\Spark\spark-3.1.1-bin-hadoop2.7\bin\spark-shell --packages neo4j-contrib:neo4j-connector-apache-spark_2.12:4.0.0
I think it work. but when I want to write the DataFrame to nodes of type Person in spark-shell:
import org.apache.spark.sql.{SaveMode, SparkSession}
val spark = SparkSession.builder().getOrCreate()
import spark.implicits._
val df = Seq(
("John Doe"),
("Jane Doe")
).toDF("name")
df.write.format("org.neo4j.spark.DataSource")
.mode(SaveMode.ErrorIfExists)
.option("url", "bolt://localhost:7687")
.option("authentication.basic.username", "neo4j")
.option("authentication.basic.password", "neo4j")
.option("labels", ":Person")
.save()
It raises errors. what should I do?
Update no. 2
I follow the steps in the 3 and it gives error when entering this:
val neo = Neo4j(sc)
as follow:
error: not found: value Neo4j
Use:
$SPARK_HOME\bin\spark-shell --conf spark.neo4j.password=<password> --packages neo4j-contrib:neo4j-spark-connector:2.4.5-M2
instead of:
$SPARK_HOME\bin\spark-shell --conf spark.neo4j.bolt.password=<password> --packages neo4j-contrib:neo4j-spark-connector:2.4.5-M2
Just remove the bolt word.
Update'
Now I want to use the following package:
$SPARK_HOME/bin/spark-shell --packages neo4j-contrib:neo4j-connector-apache-spark_2.12:4.0.1_for_spark_3
As mentioned in 1
The only one that works is the following (the old version):
$SPARK_HOME/bin/spark-shell --packages neo4j-contrib:neo4j-spark-connector:2.4.5-M2
But using it, the Neo4jGraph.saveGraph is not working. The error is : Writing in read access mode not allowed.
Thanks for your help.
I know spark related configuration can be get via spark-env.sh file however what would be the command to get it from spark-shell ?
For example to get spark.driver.memory shall I use
set spark.driver.memory
above isn't working
You can provide the memory as a configuration while launching spark-shell
spark-shell --conf spark.driver.memory=2g
This will start a spark shell with 2g of driver memory. In order to access it in spark shell, you can do the following.
val conf = sparkContext.getConf
val driverMemory = conf.get("spark.driver.memory")
This will return String = 2g.
i am trying to test spark streaming. i have stand alone cloudera quickstart vm. started the spark-shell with the following command:
spark-shell --master yarn-client --conf spark.ui.port=23123
In the spark-shell i have executed the following statements:
sc.stop()
import org.apache.spark.SparkConf
import org.apache.spark.streaming.StreamingContext
val conf = new SparkConf().setAppName("Spark Streaming")
val ssc = new StreamingContext(conf,org.apache.spark.streaming.Seconds(10))
val lines = ssc.socketTextStream("localhost",44444)
lines.print
In another terminal started the netcat service with the following command:
nc -lk 44444
In the spark-shell started the streaming context
ssc.start()
till now everything is fine. But, whatever the messages typed in the Netcat service are not received in Spark streaming.don't know where it is going wrong.
try spark-shell --master local[2] --conf spark.ui.port=23123 to see if it works.
If it works, then in your script, there is only one executor working, which is receiving message, but no executor is processing message.
I wrote a Spark application, which sets sets some configuration stuff via SparkConf instance, like this:
SparkConf conf = new SparkConf().setAppName("Test App Name");
conf.set("spark.driver.cores", "1");
conf.set("spark.driver.memory", "1800m");
conf.set("spark.yarn.am.cores", "1");
conf.set("spark.yarn.am.memory", "1800m");
conf.set("spark.executor.instances", "30");
conf.set("spark.executor.cores", "3");
conf.set("spark.executor.memory", "2048m");
JavaSparkContext sc = new JavaSparkContext(conf);
JavaRDD<String> inputRDD = sc.textFile(...);
...
When I run this application with the command (master=yarn & deploy-mode=client)
spark-submit --class spark.MyApp --master yarn --deploy-mode client /home/myuser/application.jar
everything seems to work fine, the Spark History UI shows correct executor information:
But when running it with (master=yarn & deploy-mode=cluster)
my Spark UI shows wrong executor information (~512 MB instead of ~1400 MB):
Also my App name equals Test App Name when running in client mode, but is spark.MyApp when running in cluster mode. It seems that however some default settings are taken when running in Cluster mode. What am I doing wrong here? How can I make these settings for the Cluster mode?
I'm using Spark 1.6.2 on a HDP 2.5 cluster, managed by YARN.
OK, I think I found out the problem! In short form: There's a difference between running Spark settings in Standalone and in YARN-managed mode!
So when you run Spark applications in the Standalone mode, you can focus on the Configuration documentation of Spark, see http://spark.apache.org/docs/1.6.2/configuration.html
You can use the following settings for Driver & Executor CPU/RAM (just as explained in the documentation):
spark.executor.cores
spark.executor.memory
spark.driver.cores
spark.driver.memory
BUT: When running Spark inside a YARN-managed Hadoop environment, you have to be careful with the following settings and consider the following points:
orientate on the "Spark on YARN" documentation rather then on the Configuration documentation linked above: http://spark.apache.org/docs/1.6.2/running-on-yarn.html (the properties explained here have a higher priority then the ones explained in the Configuration docu (this seems to describe only the Standalone cluster vs. client mode, not the YARN cluster vs. client mode!!))
you can't use SparkConf to set properties in yarn-cluster mode! Instead use the corresponding spark-submit parameters:
--executor-cores 5
--executor-memory 5g
--driver-cores 3
--driver-memory 3g
In yarn-client mode you can't use the spark.driver.cores and spark.driver.memory properties! You have to use the corresponding AM properties in a SparkConf instance:
spark.yarn.am.cores
spark.yarn.am.memory
You can't set these AM properties via spark-submit parameters!
To set executor resources in yarn-client mode you can use
spark.executor.cores and spark.executor.memory in SparkConf
--executor-cores and executor-memory parameters in spark-submit
if you set both, the SparkConf settings overwrite the spark-submit parameter values!
This is the textual form of my notes:
Hope I can help anybody else with this findings...
Just to add on to D. Müller's answer:
Same issue happened to me and I tried the settings with some different combination. I am running Pypark 2.0.0 on YARN cluster.
I found that driver-memory must be written during spark submit but executor-memory can be written in script (i.e. SparkConf) and the application will still work.
My application will die if driver-memory is less than 2g. The error is:
ERROR yarn.ApplicationMaster: RECEIVED SIGNAL TERM
ERROR yarn.ApplicationMaster: User application exited with status 143
CASE 1:
driver & executor both written in SparkConf
spark = (SparkSession
.builder
.appName("driver_executor_inside")
.enableHiveSupport()
.config("spark.executor.memory","4g")
.config("spark.executor.cores","2")
.config("spark.yarn.executor.memoryOverhead","1024")
.config("spark.driver.memory","2g")
.getOrCreate())
spark-submit --master yarn --deploy-mode cluster myscript.py
CASE 2:
- driver in spark submit
- executor in SparkConf in script
spark = (SparkSession
.builder
.appName("executor_inside")
.enableHiveSupport()
.config("spark.executor.memory","4g")
.config("spark.executor.cores","2")
.config("spark.yarn.executor.memoryOverhead","1024")
.getOrCreate())
spark-submit --master yarn --deploy-mode cluster --conf spark.driver.memory=2g myscript.py
The job Finished with succeed status. Executor memory correct.
CASE 3:
- driver in spark submit
- executor not written
spark = (SparkSession
.builder
.appName("executor_not_written")
.enableHiveSupport()
.config("spark.executor.cores","2")
.config("spark.yarn.executor.memoryOverhead","1024")
.getOrCreate())
spark-submit --master yarn --deploy-mode cluster --conf spark.driver.memory=2g myscript.py
Apparently the executor memory is not set. Meaning CASE 2 actually captured executor memory settings despite writing it inside sparkConf.
I have Spark running on a Cloudera CDH5.3 cluster, using YARN as the resource manager. I am developing Spark apps in Python (PySpark).
I can submit jobs and they run succesfully, however they never seem to run on more than one machine (the local machine I submit from).
I have tried a variety of options, like setting --deploy-mode to cluster and --master to yarn-client and yarn-cluster, yet it never seems to run on more than one server.
I can get it to run on more than one core by passing something like --master local[8], but that obviously doesn't distribute the processing over multiple nodes.
I have a very simply Python script processing data from HDFS like so:
import simplejson as json
from pyspark import SparkContext
sc = SparkContext("", "Joe Counter")
rrd = sc.textFile("hdfs:///tmp/twitter/json/data/")
data = rrd.map(lambda line: json.loads(line))
joes = data.filter(lambda tweet: "Joe" in tweet.get("text",""))
print joes.count()
And I am running a submit command like:
spark-submit atest.py --deploy-mode client --master yarn-client
What can I do to ensure the job runs in parallel across the cluster?
Can you swap the arguments for the command?
spark-submit --deploy-mode client --master yarn-client atest.py
If you see the help text for the command:
spark-submit
Usage: spark-submit [options] <app jar | python file>
I believe #MrChristine is correct -- the option flags you specify are being passed to your python script, not to spark-submit. In addition, you'll want to specify --executor-cores and --num-executors since by default it will run on a single core and use two executors.
Its not true that python script doesn't run in cluster mode. I am not sure about previous versions but this is executing in spark 2.2 version on Hortonworks cluster.
Command : spark-submit --master yarn --num-executors 10 --executor-cores 1 --driver-memory 5g /pyspark-example.py
Python Code :
from pyspark import SparkConf, SparkContext
from pyspark.sql import SQLContext
conf = (SparkConf()
.setMaster("yarn")
.setAppName("retrieve data"))
sc = SparkContext(conf = conf)
sqlContext = SQLContext(sc)
parquetFile = sqlContext.read.parquet("/<hdfs-path>/*.parquet")
parquetFile.createOrReplaceTempView("temp")
df1 = sqlContext.sql("select * from temp limit 5")
df1.show()
df1.write.save('/<hdfs-path>/test.csv', format='csv', mode='append')
sc.stop()
Output : Its big so i am not pasting. But it runs perfect.
It seems that PySpark does not run in distributed mode using Spark/YARN - you need to use stand-alone Spark with a Spark Master server. In that case, my PySpark script ran very well across the cluster with a Python process per core/node.