Hi all, I've been doing some testing with LoggingMemoryPool to benchmark our AsOfJoin implementation <https://github.com/apache/arrow/blob/master/cpp/src/arrow/compute/exec/asof_join_node.cc>. Our underlying memory pool for the LoggingMemoryPool is the default_memory_pool (this is process-wide).
Curiously enough, I don't see any allocations, reallocations, or frees when we run our benchmarking code. I also see that the max_memory property of the memory pool (which is documented as the peak memory allocation), is nonzero (1.2e9 bytes). My expectation is that we would see some pretty sizable calls to Allocate when we begin to read files or to create tables, but that is not evident. 1) To my understanding, only large allocations will call Allocate. Are there allocations (for files, table objects), which despite being of large size, do not call Allocate? 2) How can maximum_peak_memory be nonzero if we have not seen any calls to Allocate/Reallocate/Free? Thank you!