On 19/09/17 01:13, Dimov, Stefan wrote:
Hi,
I have Tomcat setup, that receives REST requests, “translates” them into SAPRQL
queries, invokes them on the underlying FUSEKI and returns the results:
USER AGENT
^
REST
v
---------------
TOMCAT
^
REST
v
-------------
FUSEKI
------------
JENA
-----------
TDB
----------
Would I be able to achieve significant performance improvement, if I use
directly the JENA libraries and bypass FUSEKI?
Unlikely. We successfully use the set up you describe for dozens of
services, some quite high load. We have a few which go direct to Jena
for legacy reasons and they show no particular performance benefits.
If your payloads can be large then make sure the way you are driving
fuseki is streaming and doesn't accidentally store the entire SPARQL
results in your tomcat app. This also means chosing a streamable media
type for your fuseki requests.
That said, if you have very large payload sizes from fuseki but smaller
payloads returned to the client (e.g. you do some aggregation in your
app) then there could be benefit in by-passing the second http hop to
fueski. In our cases the two REST streams are broadly comparable size
(e.g. we reformat as JSON and do some row coalescing, but any aggregates
or filters are computed in the SPARQL query not our own REST processor).
Dave
