Reduce the default min heap size and remove the default max heap size #2840
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For historical reasons we were setting the initial heap size to the same value as the max heap size: 4GiB. However, based on experimentation, our memory pool usage is around 512MB for an idle server. The cost dynamics of cloud make it more important to set an appropriate initial heap size and memory management in the JVM has gotten better over time. As for the max heap size, OpenJ9 has intelligent defaults when running within a container, and so we should use those instead of guessing at a default of our own: https://www.eclipse.org/openj9/docs/xxusecontainersupport Signed-off-by: Lee Surprenant <lmsurpre@us.ibm.com>
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For historical reasons we were setting the initial heap size to the same
value as the max heap size: 4GiB.
However, based on experimentation, our memory pool usage is only around
512MB for a lightly used ingestion workload.
The cost dynamics of cloud make it more important to set an appropriate
initial heap size and memory management in the JVM has gotten better
over time.
As for the max heap size, OpenJ9 has intelligent defaults when running
within a container, and so we should use those instead of guessing at a
default of our own:
https://www.eclipse.org/openj9/docs/xxusecontainersupport
Signed-off-by: Lee Surprenant lmsurpre@us.ibm.com