python - What happens when a spark dataframe is converted to Pandas dataframe using toPandas() method -

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this question has answer here:

i have spark dataframe can convert pandas dataframe using 

topandas()

method available in pyspark.

i have following queries regarding this?

  1. does conversion break purpose of using spark itself(distributed computing)?
  2. the dataset going huge , speed , memory issues?
  3. if can explain ,what happens 1 line of code,that help.

thanks

yes, once topandas called on spark-dataframe out of distributed system , new pandas dataframe in driver node of cluster.

and if spark-data frame huge , if doesnt fit driver memory crash.


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