Looking for the best tradeoff between the amount of operations and the latency to write them.

.md

Size operation arround 50 bytes, write concern is acknowledgment.

Bulk trhoughput vs number of update operations

2	4	8	16	32	64	128	256	512
4.5K	9K	12K	16K	19k	22K	23K	24K	27K

Bulk latence vs number of update operations

2	4	8	16	32	64	128	256	512
0.0002	0.0003	0.0004	0.0008	0.0013	0.0042	0.0043	0.0075	0.0153

The best number should be choosed taking into acount other characteristics and how these can be affected because of the above numbers such as buffer size, max latency desirable, etc.

Even that he best tradeoff between latency and throughput appears to be 32. It reaches almost 20K update operations per second and just 13ms for each bulk operation.