Spark SQL DataFrame 1.5.0 is extremely slow for take(1) or head() or first()

Hi Spark Developers, I just ran some very simple operations on a dataset. I was surprise by the execution plan of take(1), head() or first(). For your reference, this is what I did in pyspark 1.5: df=sqlContext.read.parquet("someparquetfiles") df.head() The above lines take over 15 minutes. I

Re: Spark SQL DataFrame 1.5.0 is extremely slow for take(1) or head() or first()

I just noticed you found 1.4 has the same issue. I added that as well in the ticket. On Mon, Sep 21, 2015 at 1:43 PM, Jerry Lam wrote: > Hi Yin, > > You are right! I just tried the scala version with the above lines, it > works as expected. > I'm not sure if it happens

Re: Spark SQL DataFrame 1.5.0 is extremely slow for take(1) or head() or first()

Hi Yin, You are right! I just tried the scala version with the above lines, it works as expected. I'm not sure if it happens also in 1.4 for pyspark but I thought the pyspark code just calls the scala code via py4j. I didn't expect that this bug is pyspark specific. That surprises me actually a

Re: Spark SQL DataFrame 1.5.0 is extremely slow for take(1) or head() or first()

Looks like the problem is df.rdd does not work very well with limit. In scala, df.limit(1).rdd will also trigger the issue you observed. I will add this in the jira. On Mon, Sep 21, 2015 at 10:44 AM, Jerry Lam wrote: > I just noticed you found 1.4 has the same issue. I

Re: Spark SQL DataFrame 1.5.0 is extremely slow for take(1) or head() or first()

Seems 1.4 has the same issue. On Mon, Sep 21, 2015 at 10:01 AM, Yin Huai wrote: > btw, does 1.4 has the same problem? > > On Mon, Sep 21, 2015 at 10:01 AM, Yin Huai wrote: > >> Hi Jerry, >> >> Looks like it is a Python-specific issue. Can you create

Re: Spark SQL DataFrame 1.5.0 is extremely slow for take(1) or head() or first()

btw, does 1.4 has the same problem? On Mon, Sep 21, 2015 at 10:01 AM, Yin Huai wrote: > Hi Jerry, > > Looks like it is a Python-specific issue. Can you create a JIRA? > > Thanks, > > Yin > > On Mon, Sep 21, 2015 at 8:56 AM, Jerry Lam wrote: > >> Hi

Re: Spark SQL DataFrame 1.5.0 is extremely slow for take(1) or head() or first()

Hi Jerry, Looks like it is a Python-specific issue. Can you create a JIRA? Thanks, Yin On Mon, Sep 21, 2015 at 8:56 AM, Jerry Lam wrote: > Hi Spark Developers, > > I just ran some very simple operations on a dataset. I was surprise by the > execution plan of take(1),