Marco I don’t believe anyone has tried to contact them yet
I think that the complaints here are that there doesn’t appear to have been any attempt to report the issues identified back to the projects studied. If this was a security flaw in the project the standard Industry and research practice would be to make a responsible disclosure to the projects in advance of the public disclosure such that the researchers and projects can work together to resolve the problem. The implication being that it is irresponsible for the authors to benefit from pointing out flaws in the projects while appearing to make no efforts to help report/resolve those issues. As you suggest this paper does appear to be based upon some thesis work, that thesis indicates that the research was originally carried out in 2015 implying that the author knew of the issue two years ago. The project has a relatively small core of developers most of whom work on Jena on the side. We very much rely upon the wider community to provide input on bugs that need to be resolved e.g. Performance issues and the features we should prioritise. When someone clearly knew of a problem but didn’t tell us that is inevitably frustrating for the project. Rob On 19/10/2017 10:08, "Marco Neumann" <[email protected]> wrote: did you try to contact Daniel Janke, Adrian Skubella or Steffen Staab to get a response? the findings seem to based on work that has been published online as part of a bachelor’s thesis by Adrian Skubella. https://west.uni-koblenz.de/sites/default/files/studying/theses-files/bachelorarbeit-adrian-skubella-benchmarks-for-sparql-property-paths.pdf On Thu, Oct 19, 2017 at 10:54 AM, Lorenz B. <[email protected]> wrote: > For me this is really bad practice. It also looks like they did the > benchmark more than one year ago. Otherwise due to JENA-1195 this error > wouldn't occur anymore. And submission deadline was August 6th, 2017 . > Their experiments contain 8 queries, rerunning those shouldn't take ages... > > I'm currently trying to reproduce the results of the paper, but the > whole experimental setup remains unclear. I'm wondering if they used > just the Jena CLI or TDB. The same holds for RDF4J. I'm puzzled because > the runtimes in the eval section are quite small, but even loading the > data of their benchmark takes much more time. So maybe they used the > RDF4J server. > > The worst thing is that they didn't contact any of the developers. Or > did they talk to somebody here and then Andy created the ticket > JENA-1195? Also for the other queries that failed, I would expect to see > tickets on Apache JIRA or at least a hint on the Jena mailing list... > > @Andy I'm also wondering whether JENA-1317 addresses the problem with > the empty result of benchmark query containing an inverse property path. > > > On 18.10.2017 17:03, [email protected] wrote: >> As you know, Andy, I'm going to ISWC this year-- shall I buttonhole >> them and give them our POV? :grin: >> >> In all seriousness, from what I can tell the results amount to "Using >> older versions of our comparands and without contacting the projects >> in question we couldn't find a store that implements every property >> path feature correctly and some fail entirely." >> >> I'm not really sure how useful that information is...? But I am ready >> to do a benchmarking paper for next year. Seems like it's a lot easier >> than I thought! >> >> >> ajs6f >> >> >> Andy Seaborne wrote on 10/17/17 9:28 AM: >>> Hi Lorenz, >>> >>> Looks like JENA-1195 which is fixed. Does that look like it? >>> >>> I think it is shame when papers focus on bugs rather than discussing >>> and even fixing them. Bugs aren't research. >>> >>> Path evaluation could improved to stream in more cases (that's why >>> LIMIT didn't help), but 1195 explains the slowness >>> and memory. >>> >>> Andy >>> >>> On 17/10/17 07:58, Lorenz B. wrote: >>>> Hi, >>>> >>>> I just walked through the papers for the upcoming ISWC conference and >>>> found a paper about benchmarking of SPARQL property paths [1] . >>>> >>>> Not sure if this is relevant, but it looks like Jena has some issues >>>> with different types of queries using the property path. For example, >>>> >>>> SELECT ?o WHERE {A B* ?o.} LIMIT 100 >>>> >>>> lead to an OOM error on non-cyclic data. Here is the relevant part of >>>> the paper: >>>> >>>>> While benchmarking Virtuoso, RDF4J and Allegrograph no errors or >>>>> exceptions have occurred. During the benchmark process of Jena an >>>>> OutOfMemoryError has been thrown whenever a query with the * operator >>>>> was used. In order to identify the cause of the error, the amount of >>>>> results the query should return has been limited to 100. The results >>>>> that have been returned by a query of the form SELECT ?o WHERE {A B* >>>>> ?o.} LIMIT 100 where A and B are valid IRIs, consisted of 100 times A. >>>>> Due to this fact it is presumable that the query containing the * >>>>> operator returns A recursively until the main memory was full. To >>>>> ensure that this behaviour is not caused by cycles in the dataset a >>>>> query of the same form but with a predicate IRI that did not exist in >>>>> the dataset was executed. This query still returned 100 times A. This >>>>> indicates, that the * operator is not implemented correctly. >>>> In addition, the experiments showed that: >>>>> Due to the problems with the * operator the queries 4, 7 and 8 could >>>>> not be processed. Additionally query 3, 5, and 6 returned no results >>>>> after 1 hour and thus, were aborted. Query 1 returned an empty and >>>>> thus, incomplete result set. Only for query 2 a valid result was >>>>> returned. Due to the lack of comparable results, Jena has been omitted >>>>> in the comparison of triple stores. >>>> >>>> In the discussion section, they summarize the overall performance of >>>> Jena by >>>> >>>>> Jena could not return results for any query in under 1 hour besides >>>>> query 2. Furthermore, the * operator could not be evaluated at all and >>>>> the inverse operator returned empty result sets. >>>> >>>> It looks like they used version 3.0.1, so maybe this doesn't hold >>>> anymore for all of the queries. If not, it could be interesting to >>>> improve performance and/or completeness. >>>> >>>> I hope I didn't miss some open JIRA ticket, but in general I just >>>> wanted >>>> to highlight the presence of some published benchmark for those kind of >>>> queries. >>>> >>>> >>>> Cheers, >>>> >>>> Lorenz >>>> >>>> [1] http://ceur-ws.org/Vol-1932/paper-04.pdf >>>> > -- --- Marco Neumann KONA
