Allocation profiling skip allocations

[franz1981]

Giving this reproducer

public class Alloc {

     private static volatile Object objs;	

     public static void main(String[] args) {
     	Object[] obj = new Object[1*1000*1000];
     	for (int i = 0; i < obj.length; i++) {
     	       obj[i] = new Object();
     	}
     	objs = obj;     	
     }
}

Before 6dfd215 if we run:

$ java  -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC -XX:-UseTLAB -agentpath:<right path>/libasyncProfiler.so=start,event=alloc,file=alloc.html Alloc.java

it reported something like

which is both right in term of colors and magnitude (1_000_000 Object and 1 Object[]).
To be sure that I could see Object[] I have used the jfr format and extracted total, reporting

16_000_000 bytes for Object and 4_000_0016 bytes for Object[]

but after 6dfd215 it become

with 30 samples of Object and 1 sample for Object[].

I've used

java version "17.0.7" 2023-04-18 LTS
Java(TM) SE Runtime Environment (build 17.0.7+8-LTS-224)
Java HotSpot(TM) 64-Bit Server VM (build 17.0.7+8-LTS-224, mixed mode, sharing)

Thanks @radcortez to have found it!

[apangin]

That's by design.
The default allocation sampling interval is 512KB. If you want to count every allocation, set the sampling interval to 1:

java -XX:-UseTLAB -agentlib:asyncProfiler=start,alloc=1,total,file=alloc.html Alloc.java

[franz1981]

Sorry @apangin I missed this change in behaviour!