A box containing the word “SQL” points to a box containing the words “Oracle Net Services Client Access.” This box points to a box labeled “DBMPERF Service.” Inside this box are Node 1, Node 2, and Node 3. Below is a disk labeled PARALLEL_INSTANCE_GROUP=imperf. The disk points to the three nodes. The arrow is labeled “In-Memory Population and Buffer Cache I/O.” The disk also points to Node 4. The arrow is labeled “Buffer Cache I/O Only.”