Unknown/Junk binary documents are present in _default collection.

Steps:

1. Create a 1 node cluster and a magma bucket with 256MB ram and 2 collections.
2. Start data loading json docs at 200 ops per sec(100/s in each collections) while doc size in 1024 bytes and key size is 18 bytes.
3. A lot of binary documents are seen _default collection while there is nothing loaded in _default collection during the data loading in the test.

Another observation is I have 2 cluster running the exactly same test. the only difference is the doc value size.
Cluster with 1024 doc value size - This issue is seen
Cluster with 512 doc value size - This issue is NOT seen

Snapshot from 1024 value size cluster(http://172.23.110.64:8091/ui/index.html#/buckets?commonBucket=GleamBookUsers0&scenarioZoom=hour&scenario=kdnv162ws):

Snapshot from 512 value size cluster(http://172.23.110.127:8091/ui/index.html#/buckets?commonBucket=GleamBookUsers0&scenarioZoom=hour&scenario=igmv156ey):