Hi, I have found a problem while using qthreads with gastnet, to make it simpler I will consider only one locale, but when more are used the problem is exactly the same.
The platform is a cluster of locales (each with 16 cores and 64 GBytes of RAM). More precisely, each locale has two sockets with 8 cores each and Hyper-Threading has been disabled. The Chapel program has just these two lines: ---- use Time; sleep(50); ---- When compiled with gasnet, two threads use 100% of CPU while the sleep is executed, with one of them using about 34.9%user, 62.5%sys, and the other 100% user. I ended up checking this simple chapel code because for another (more realistic) application, I obtained some scalability when moving from 1 to 8 threads per locale, but execution time increase if I use more than 8 threads although, as I said, the locale has 16 cores. Any thoughts? Thank you very much in advance, Rafael -- Rafael Larrosa Jiménez Centro de Supercomputación y Bioinformática - http://www.scbi.uma.es Universidad de Málaga EMAIL: [email protected] Edificio de Bioinnovación TELEF: + 34951952788 C/ Severo Ochoa 34 FAX : +34951952792 Parque Tecnológico de Andalucía 29590 Málaga (SPAIN) ------------------------------------------------------------------------------ _______________________________________________ Chapel-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/chapel-developers
