Hello Christophe, I am relatively new to Fuseki, so take my feedback with a grain of salt.
I recall reading that Fuseki accumulates updates in memory while readers are active, and that only when there are no readers does it apply accumulated updates. This means that if you have a multi-threaded application with frequent reads and writes, you will likely gradually fill up memory until there’s a pause in reading and there’s a chance to write out the accumulated updates. I experienced this with an application I was running with 30 threads in parallel. It filled up my workstation’s memory, and my workstation crashed. I reduced the number of concurrent threads to 1, and the problem did not recur. You could try reducing the number of threads, or try pausing all readers—if that’s possible—to give Fuseki a chance to write out accumulated updates. All the best Ted Theodore Hills Consultant | Research Phone: +1 212 296-1833 [email protected]<mailto:[email protected]> From: christophe heligon <[email protected]> Sent: Thursday, October 20, 2022 7:30 AM To: users <[email protected]> Subject: Memory leak in fuseki? (attached file included) Hi everyone, I am using Apache Jena Fuseki 4.6.1 to host 2 datasets (rdf + rdf-star). I have noticed an unexpected behaviour on my server as my RAM gets filled little by little over time ( 100 Mo / few minutes can be several Go at the end) when no queries are received by the server. When I submit a query using fuseki GUI the RAM gets freed (at least partially) from what seemed to have accumulated into it in between queries. The java process is using that memory see attached file. Note that I use the standard configuration provided by the server except for the max memory that I set to 20 Go. The java process is largely exceeding this limit as it may reach over 50 Go. Is it a known issue of Fuseki? Java? Is there a way to monitor that better than just record memory use? Any fix published or hint on how to solve that? Best regards, Christophe -- [https://igdr.univ-rennes1.fr/sites/igdr.univ-rennes1.fr/files/medias/images/logoIGDR.jpg] Christophe Héligon Institut de Génétique & Développement de Rennes Equipe Ingénierie Inverse de la Division Cellulaire (CeDRE) [https://igdr.univ-rennes1.fr/sites/igdr.univ-rennes1.fr/files/medias/images/email-icon-2x.png] [email protected]<mailto:[email protected]> [https://igdr.univ-rennes1.fr/sites/igdr.univ-rennes1.fr/files/medias/images/link-icon-2x.png] https://igdr.univ-rennes1.fr [https://igdr.univ-rennes1.fr/sites/igdr.univ-rennes1.fr/files/medias/images/address-icon-2x.png] UMR 6290 CNRS - UR1, ERL Inserm U1305 Campus Santé de Villejean, 2 avenue du Professeur Léon Bernard, CS 34317 / 35043 Rennes Cedex, France ________________________________ For important information including analyst certification and disclosures regarding specific companies, derivatives, or other instruments discussed in this email, please refer to the latest report, if attached and/or hyperlinked to this email, or by logging on to the Morgan Stanley Matrix Platform at http://matrix.ms.com/eqr/research . You may also refer to the Morgan Stanley Research Disclosure Website at http://www.morganstanley.com/eqr/disclosures/webapp/coverage. Morgan Stanley will make certain research products and announcements available only on the Morgan Stanley Matrix Platform. The content provided in this email, including data or any attachments, is subject to the terms and conditions of use (available at https://ny.matrix.ms.com/matrix/portal/docs/terms/index.html#/terms/general ) applicable to research materials accessed through Matrix, including the terms regarding confidentiality and intellectual property rights. For access to the Morgan Stanley Matrix Platform please contact your sales representative or go to Matrix. NOTICE: Morgan Stanley is not acting as a municipal advisor and the opinions or views contained herein are not intended to be, and do not constitute, advice within the meaning of Section 975 of the Dodd-Frank Wall Street Reform and Consumer Protection Act. If you have received this communication in error, please destroy all electronic and paper copies and notify the sender immediately. Mistransmission is not intended to waive confidentiality or privilege. Morgan Stanley reserves the right, to the extent permitted under applicable law, to monitor electronic communications. This message is subject to terms available at the following link: http://www.morganstanley.com/disclaimers If you cannot access these links, please notify us by reply message and we will send the contents to you. By messaging with Morgan Stanley you consent to the foregoing. You may have certain rights regarding the information that Morgan Stanley collects about you. Please see our Privacy Pledge https://www.morganstanley.com/privacy-pledge for more information about your rights.
