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Impala JVM full garbage collection

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Impala JVM full garbage collection

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Hi, 

 

Running Impala version 2.2.0-cdh5.

 We're noticing some significant FGC delays across embedded JVMs in Impala daemons:

S0   S1    E     O     P     YGC  YGCT    FGC FGCT    GCT     LGCC               GCC 
 0.00 83.80 62.51 97.86 98.61 1085 141.564 39 177.707 319.272 Allocation Failure No GC 
0.00 83.80 99.33 97.86 98.62 1085 141.564 39 177.707 319.272 Allocation Failure No GC
68.33 0.00 9.24 89.14 98.58 1086 142.605 40 194.752 337.357 Allocation Failure No GC

Since the FGC is 'stop the world' and is taking over 15 seconds to complete, we're concerned this is a factor affecting Impala query speed.

 

Does someone smarter than I have any ideas on corrective action or causastion? 

 

Thanks