bq. The total size by class B is 3GB in 1.5.1 and only 60MB in 1.6.0. >From the information you posted, it seems the above is backwards.
BTW [B is byte[], not class B. FYI On Thu, Jan 28, 2016 at 11:49 AM, Jesse F Chen <jfc...@us.ibm.com> wrote: > I ran the same streaming application (compiled individually for 1.5.1 and > 1.6.0) that processes 5-second tweet batches. > > I noticed two things: > > 1. 10% regression in 1.6.0 vs 1.5.1 > > Spark v1.6.0: 1,564 tweets/s > Spark v1.5.1: 1,747 tweets/s > > 2. 1.6.0 streaming seems to have a memory leak. > > 1.6.0, processing time gradually increases and eventually exceeds 5 > seconds so batches started to queue up. > While in 1.5.1, no such slow down. See chart below to see the increasing > scheduling delay in 1.6: > > > > I captured heap dumps in two version and did a comparison. I noticed the > Byte base class is using 50X more space in 1.5.1. > > Here are some top classes in heap histogram and references. > > Heap Histogram > > All Classes (excluding platform) > 1.6.0 Streaming 1.5.1 Streaming > Class Instance Count Total Size Class Instance Count Total Size > class [B 8453 *3,227,649,599 * class [B 5095 62,938,466 > class [C 44682 4,255,502 class [C 130482 12,844,182 > class java.lang.reflect.Method 9059 1,177,670 class java.lang.String > 130171 1,562,052 > > > References by Type References by Type > > class [B [0x640039e38] class [B [0x6c020bb08] > > Referrers by Type Referrers by Type > > Class Count Class Count > java.nio.HeapByteBuffer *3239* sun.security.util.DerInputBuffer 1233 > sun.security.util.DerInputBuffer 1233 sun.security.util.ObjectIdentifier > 620 > sun.security.util.ObjectIdentifier 620 [[B 397 > [Ljava.lang.Object; 408 java.lang.reflect.Method 326 > > > ---- > > The total size by class B is 3GB in 1.5.1 and only 60MB in 1.6.0. > The Java.nio.HeapByteBuffer referencing class did not show up in top in > 1.5.1. > > I have also placed jstack output for 1.5.1 and 1.6.0 online..you can get > them here > > https://ibm.box.com/sparkstreaming-jstack160 > https://ibm.box.com/sparkstreaming-jstack151 > > Jesse > > > > > > >
