Can you please attach the full query profiles? 

Thanks 
Mostafa

> On Jan 3, 2018, at 8:20 AM, Tim Armstrong <[email protected]> wrote:
> 
> That's a tricky one. I have a couple of ideas but it's a bit difficult to 
> confirm since the profile isn't really designed to easily answer questions 
> like this. ProbeTime measures wall-clock time rather than actual time spent 
> executing on the CPU.
> 
> My first guess is that it's because the Kudu scan is using more CPU than the 
> Parquet scan and ProbeTime so the thread doing the scan is competing for 
> resources more with the join thread (either hyperthreads competing for 
> resources on the same CPU or threads competing for time on logical 
> processors). You could compare the User CPU time for the fragment instances 
> containing the joins and scans to see if there is also a discrepancy in CPU 
> time. That won't answer this directly but might provide some clues.
> 
> My second guess is that there's some kind of subtle memory locality or 
> scheduling effect.
> 
>> On Tue, Jan 2, 2018 at 11:40 PM, helifu <[email protected]> wrote:
>> Hi everybody,
>> 
>>  
>> 
>> Recently I ran a simple PHJ on‘parquet’ and ‘kudu’with this sql 
>> independently:
>> 
>> select count(*) from lineitem as l, orders as o where l.l_orderkey = 
>> o.o_orderkey and o.o_orderdate < '1996-01-01' and o.o_orderdate >= 
>> '1995-01-01';
>> 
>>  
>> 
>> And I found that the ‘ProbeTime’ on ‘kudu’is much larger than on ‘parquet’!!
>> 
>> 
>> 
>> 
>> 
>>  
>> 
>> Below are the plans and profiles:
>> 
>> 
>> 
>>  
>> 
>> Thanks in advance.
>> 
>>  
>> 
>>  
>> 
>> 何李夫
>> 
>> 2017-04-10 16:06:24
>> 
>>  
>> 
> 

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