Github user Ben-Zvi commented on a diff in the pull request:
https://github.com/apache/drill/pull/938#discussion_r138492663
--- Diff:
exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/aggregate/HashAggTemplate.java
---
@@ -646,6 +687,46 @@ public AggOutcome doWork() {
}
/**
+ * Use reserved values memory (if available) to try and preemp an OOM
+ */
+ private void useReservedValuesMemory() {
+ // try to preempt an OOM by using the reserved memory
+ long reservedMemory = reserveValueBatchMemory;
+ if ( reservedMemory > 0 ) { allocator.setLimit(allocator.getLimit() +
reservedMemory); }
+
+ reserveValueBatchMemory = 0;
+ }
+ /**
+ * Use reserved outgoing output memory (if available) to try and
preemp an OOM
+ */
+ private void useReservedOutgoingMemory() {
+ // try to preempt an OOM by using the reserved memory
+ long reservedMemory = reserveOutgoingMemory;
+ if ( reservedMemory > 0 ) { allocator.setLimit(allocator.getLimit() +
reservedMemory); }
+
+ reserveOutgoingMemory = 0;
+ }
+ /**
+ * Restore the reserve memory (both)
+ *
+ */
+ private void restoreReservedMemory() {
+ if ( 0 == reserveOutgoingMemory ) { // always restore OutputValues
first (needed for spilling)
+ long memAvail = allocator.getLimit() -
allocator.getAllocatedMemory();
+ if ( memAvail > estOutgoingAllocSize) {
+ allocator.setLimit(allocator.getLimit() - estOutgoingAllocSize);
--- End diff --
Can never add twice, as the code only adds to an empty ( == 0 ) reserve.
And these are not "relative deltas", but the actual expected batch size (so
that the following allocation would not OOM).
---
