• Database contains a simple collection containing only three fields: the normal bson id, a 10-character unique identifier (indexed), and a text field that typically holds a ~10k string (raw xml)
• This collection has ~350k records, reporting a total 3.6GB size
• Dumping this collection with mongodump, using "mongodump -d mydatabase -c mycollection -o destination" causes memory to rapidly grow by ~4GB during the dump, and is never released.
• The same behavior is observed on both mac and windows environments

Let me know what additional details I can provide that might be helpful.