Regarding Humongous Allocation - G1GC

[Ravi]

Dear Experts,

We have an application running on jre 1.8u261 with the below jvm arguments:
 -Xms8g -Xmx8g -XX:MetaspaceSize=2g -XX:MaxMetaspaceSize=2g -XX:+UseG1GC
-XX:ParallelGCThreads=2 -XX:ConcGCThreads=1 -XX:+PrintFlagsFinal

>From the jfrs, we could see Humongous allocation failures are happening in
the G1New and aswell G1Old spaces:
GC ID Cause Collector Name Longest Pause Sum of Pauses Final References Weak
References Soft References Phantom References Duration Start Time End Time Used
Heap Before GC Used Heap After GC Used Heap Delta Duration in seconds
7,156 G1 Humongous Allocation G1New 164.046 ms 164.046 ms 128 3 0 0
164.046 ms 7/22/24, 3:53:52.858 AM 7/22/24, 3:53:53.022 AM 3.73 GiB 3.33 GiB
-407 MiB 0.164046
7,157 G1 Humongous Allocation G1Old 182.956 ms 197.682 ms 3 72,074 3,638 24
2.831 s 7/22/24, 3:53:52.858 AM 7/22/24, 3:53:55.689 AM 3.73 GiB 2.58 GiB
-1.14 GiB 2.831
7,178 G1 Humongous Allocation G1New 88.197 ms 88.197 ms 4 4 0 0 88.197
ms 7/22/24,
3:54:05.838 AM 7/22/24, 3:54:05.926 AM 3.74 GiB 3.49 GiB -258 MiB 0.088197
7,179 G1 Humongous Allocation G1Old 183.655 ms 197.983 ms 1 71,947 3,640 24
2.558 s 7/22/24, 3:54:05.838 AM 7/22/24, 3:54:08.396 AM 3.74 GiB 2.66 GiB
-1.08 GiB 2.558

But the java tuning document mentions that humongous allocation happens in
the old generation. How do we interpret this above data? Under which
circumstances do we see this kind of behaviour (humongous allocation
failure in g1new space),
ref:
https://docs.oracle.com/javase/8/docs/technotes/guides/vm/gctuning/g1_gc_tuning.html

Could you please throw some light.

Thanks in advance
Ravi
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