Hi,
Robin Schumacher at DataStax is trying to dispel confusions around the
difference between Gremlin OLTP and Gremlin OLAP. Here is what I wrote him, I
thought others might like to read it.
As it relates to Gremlin's execution environment.
OLTP: Serial stream processing.
OLAP: Parallel step-wise processing.
OLTP: Low memory footprint, lazy evaluator.
OLAP: High memory footprint, eager evaluator.
OLTP: Touches as little data as possible, low strain on the database.
OLAP: Touches a lot of data, high strain on the database.
OLTP: "Pointer chasing" to enact a traversal.
OLAP: Full "table" scans with message passing to enact a traversal.
OLTP: Database can support numerous concurrent traversals.
OLAP: Database can support few concurrent traversals.
OLTP: Millisecond/second response times.
OLAP: Minute/hour response times.
OLTP: Uses DSEGraph ?Thrift? driver to fetch data.
OLAP: Uses DSEGraph?CassandraInputFormat? table scanner to fetch data.
Why OLTP or OLAP?
When your query is going to touch everything in the graph, go OLAP.
Examples include PageRank, BulkLoading, BulkDumping, Global analytics.
- "What is the average number of friends for all people?"
When your query is going to touch a very small part of the graph, go
OLTP. Examples include personalized recommendations, local queries, get/put
behaviors.
- "What is the average number of friends for people that work
for DataStax?"
HTH,
Marko.
http://markorodriguez.com
