Fuseki service vs. webapp

[Sorin Gheorghiu]

Hi,

Let's suppose Fuseki 3.6.0 is started as a service (and specific plugins 
like reindex, percolator, mustache, netty3 & 4 are loaded). Then a 
script which reads intensively data over SPARQL fails after the first 
~400 SELECT's with connection refused error 
(Net::HTTP::Persistent::Error). It seems due to too many client 
connections in use fuseki is not capable to open new ones.

If the log4j is set to DEBUG (instead INFO or WARN) the script won't 
crash, but fuseki will generate a huge amount of debug data which 
produces a process delay which helps it to close the old connections. Of 
course, this is not a reliable workaround on a production server.

Alternatively, if fuseki is started as a Webapp (for the same assembler 
file), then the same script runs (more than 80000 SELECT's within 1 
hour) without failure. In conclusion, fuseki as a Web Application 
handles better the client connections.

Regards,
Sorin