-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 We (data.ox.ac.uk) do query throttling at the application level; each IP has an 'intensity' score, increased by the duration of each query, but which decays over time (at a rate of 0.05s/s). Once this hits fifteen seconds we delay the query, and once it hits thirty we refuse it (but include a Retry-After header). This should slow down the very intensive agents, but leave most people well alone. Here's the code:
https://github.com/ox-it/humfrey/blob/master/humfrey/sparql/views/core.py#L172 I do intend to get query timeouts working, but I'd like to set them per-request (as far as Fuseki is concerned). This needs me to find the time to finish off JENA-218. This will allow me to trust logged in users with longer timeouts, and have no timeouts on pages where the user doesn't get to specify the query. I also asked about this back in the day on answers.semanticweb.com; the answers there might be quite useful: http://answers.semanticweb.com/questions/3771 That said, I don't think we've ever had problems with excessive querying. Most expensive querying will be the result of naïveté ("give me everything", non-overlapping joins), and the only time I've noticed that is when it's been me making the mistake. Maybe as more people cotton on to SPARQL it'll become more of an issue for us… Best regards, Alex On 29/11/12 21:41, Sarven Capadisli wrote: > I would like to better control over my public SPARQL Endpoints > (using Fuseki) due to some harmless looking, but expensive queries > coming in. My initial thoughts were, and not necessarily the ones I > want to take: > > * Block the IP or agent * Use default query timeout values * Start > using API keys or other authentication * Catch the exact queries > from httpd and block it off * Handle certain query types from > Fuseki or TDB > > But, more importantly, I'd love to her some of the actions you all > take on your endpoints. If you can point me to any documentation or > some of the common practices out there, that'd be awesome as well. - -- Alexander Dutton Developer, Office of the CIO; data.ox.ac.uk, OxPoints IT Services, University of Oxford, ℡ 01865 (6)13483 -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://www.enigmail.net/ iQEcBAEBAgAGBQJQuJlQAAoJEPotabD1ANF7bwEH/Rg8+JQ5wiLbeg17K35jXUgv rpUKZPJCV+TpndVn9apnqn50n4bcddmqSNYhVWV5XF7vV9gNY4mf4OLcJhJI3kMP 2ddAqeQKRVb0RoWV+HLPoqawFxzO8hVf5ls5ZOPYt9imhhGRzAbAxqaG86pXeFUi w+df+CBjSZj4JZCKRMkk6WLw0Q0dj6G+rk5c46FrdUu3AUlBPAw38yHnWeE2f66l NBNiAAz7i6F6Cz0MzzAg6/A9MqO8jG0RSRE2EWpHf42uGJ5Qn9d1muFgdZtRTjUA DeQ93gRP/Oh/iMXlxi41Ql1/YdfRRXrxmL35QezJ7vY2stjfaJRwUjzXpmbA1nY= =s0gc -----END PGP SIGNATURE-----
