Re: Enabling mapreduce.input.fileinputformat.list-status.num-threads in Spark?

[Alex Nastetsky]

Ran into this need myself. Does Spark have an equivalent of  "mapreduce.
input.fileinputformat.list-status.num-threads"?

Thanks.

On Thu, Jul 23, 2015 at 8:50 PM, Cheolsoo Park  wrote:

> Hi,
>
> I am wondering if anyone has successfully enabled
> "mapreduce.input.fileinputformat.list-status.num-threads" in Spark jobs. I
> usually set this property to 25 to speed up file listing in MR jobs (Hive
> and Pig). But for some reason, this property does not take effect in Spark
> HadoopRDD resulting in serious delay in file listing.
>
> I verified that the property is indeed set in HadoopRDD by logging the
> value of the property in the getPartitions() function. I also tried to
> attach VisualVM to Spark and Pig clients, which look as follows-
>
> In Pig, I can see 25 threads running in parallel for file listing-
> [image: Inline image 1]
>
> In Spark, I only see 2 threads running in parallel for file listing-
> [image: Inline image 2]
>
> What's strange is that the # of concurrent threads in Spark is throttled
> no matter how high I
> set "mapreduce.input.fileinputformat.list-status.num-threads".
>
> Is anyone using Spark with this property enabled? If so, can you please
> share how you do it?
>
> Thanks!
> Cheolsoo
>

Re: Enabling mapreduce.input.fileinputformat.list-status.num-threads in Spark?

[Cheolsoo Park]

Alex, see this jira-
https://issues.apache.org/jira/browse/SPARK-9926

On Tue, Jan 12, 2016 at 10:55 AM, Alex Nastetsky <
alex.nastet...@vervemobile.com> wrote:

> Ran into this need myself. Does Spark have an equivalent of  "mapreduce.
> input.fileinputformat.list-status.num-threads"?
>
> Thanks.
>
> On Thu, Jul 23, 2015 at 8:50 PM, Cheolsoo Park 
> wrote:
>
>> Hi,
>>
>> I am wondering if anyone has successfully enabled
>> "mapreduce.input.fileinputformat.list-status.num-threads" in Spark jobs. I
>> usually set this property to 25 to speed up file listing in MR jobs (Hive
>> and Pig). But for some reason, this property does not take effect in Spark
>> HadoopRDD resulting in serious delay in file listing.
>>
>> I verified that the property is indeed set in HadoopRDD by logging the
>> value of the property in the getPartitions() function. I also tried to
>> attach VisualVM to Spark and Pig clients, which look as follows-
>>
>> In Pig, I can see 25 threads running in parallel for file listing-
>> [image: Inline image 1]
>>
>> In Spark, I only see 2 threads running in parallel for file listing-
>> [image: Inline image 2]
>>
>> What's strange is that the # of concurrent threads in Spark is throttled
>> no matter how high I
>> set "mapreduce.input.fileinputformat.list-status.num-threads".
>>
>> Is anyone using Spark with this property enabled? If so, can you please
>> share how you do it?
>>
>> Thanks!
>> Cheolsoo
>>
>
>

Re: Enabling mapreduce.input.fileinputformat.list-status.num-threads in Spark?

[Alex Nastetsky]

Thanks. I was actually able to get mapreduce.input.
fileinputformat.list-status.num-threads working in Spark against a regular
fileset in S3, in Spark 1.5.2 ... looks like the issue is isolated to Hive.

On Tue, Jan 12, 2016 at 6:48 PM, Cheolsoo Park  wrote:

> Alex, see this jira-
> https://issues.apache.org/jira/browse/SPARK-9926
>
> On Tue, Jan 12, 2016 at 10:55 AM, Alex Nastetsky <
> alex.nastet...@vervemobile.com> wrote:
>
>> Ran into this need myself. Does Spark have an equivalent of  "mapreduce.
>> input.fileinputformat.list-status.num-threads"?
>>
>> Thanks.
>>
>> On Thu, Jul 23, 2015 at 8:50 PM, Cheolsoo Park 
>> wrote:
>>
>>> Hi,
>>>
>>> I am wondering if anyone has successfully enabled
>>> "mapreduce.input.fileinputformat.list-status.num-threads" in Spark jobs. I
>>> usually set this property to 25 to speed up file listing in MR jobs (Hive
>>> and Pig). But for some reason, this property does not take effect in Spark
>>> HadoopRDD resulting in serious delay in file listing.
>>>
>>> I verified that the property is indeed set in HadoopRDD by logging the
>>> value of the property in the getPartitions() function. I also tried to
>>> attach VisualVM to Spark and Pig clients, which look as follows-
>>>
>>> In Pig, I can see 25 threads running in parallel for file listing-
>>> [image: Inline image 1]
>>>
>>> In Spark, I only see 2 threads running in parallel for file listing-
>>> [image: Inline image 2]
>>>
>>> What's strange is that the # of concurrent threads in Spark is throttled
>>> no matter how high I
>>> set "mapreduce.input.fileinputformat.list-status.num-threads".
>>>
>>> Is anyone using Spark with this property enabled? If so, can you please
>>> share how you do it?
>>>
>>> Thanks!
>>> Cheolsoo
>>>
>>
>>
>