> On 2021-07-05, at 11:01:34, Ivan Lagunov <[email protected]> wrote: > > Hello, > > We’re facing an issue with Jena reading n-triples stream over HTTP. In fact, > our application hangs entirely while executing this piece of code: > > ... > > The issue is not persistent, moreover it happens infrequently. When it > occurs, the RDF store server (we use Dydra for that) logs a successful HTTP > 200 response for our call (truncated for readability): > HTTP/1.1" 200 3072/55397664 10.676/10.828 "application/n-triples" "-" "-" > "Apache-Jena-ARQ/3.17.0" "127.0.0.1:8104"
an additional detail appears in other nginx log entries. the two values "10.676/10.828", above, are nginx's upstream response time and the client connection time. it can be the case that, for problematic requests, the second value is significantly higher than the first. this would indicate that nginx has received a complete response from the upstream connection, but required a much longer time to complete sending the data to the client. as, however, none of the examined entries indicated a 499 status, it appears that the client was sent all data. this may indicate some anomaly in the encoding, respective decoding, for which a stack trace at the point of the "timeout" would be a valuable diagnostic. --- james anderson | [email protected] | https://dydra.com
