There is growth of jemalloc resident memory when indexer performs many metadata operations. Steps to reproduce:
1. setup 1 node cluster with kv+n1ql+index with MOI and large memory quota.
2. create 30 indexes with defer build (no need to build indexes).
3. delete 30 indexes.
After repeating steps (2) and (3) ~50 times, jemalloc resident memory reaches ~220MB. The attached jemalloc profile (jemalloc-101.prof.svg) shows that most of the memory is allocated by fdb_iterator_init() and fdb_snapshot_open().