Now this is a interesting question. As it happens I /am/ blindly assuming the os would schedule it properly. I will look at my options this evening and see about addressing that.
On Mar 3, 2017 4:52 PM, Keith Medcalf <kmedc...@dessus.com> wrote: No, the good rule of thumb is to allocate one thread per CPU. Depending on the particular multi-core CPU you "may" be able to use all the cores simultaneously but in many cases diminishing returns will set in long before you can execute one thread per core. If this is an Intel processor that claims it has more than one thread per core be *extremely* careful as that will give you one thread and one half-assed thread per core. Sometimes, half-assed cores are presented as real cores when they lack a separate execution unit. Be vary wary. I presume you are forcing separate threads to separate cores by setting processor affinity on the threads and not just blindly hoping that the OS scheduler does "the right thing"? > -----Original Message----- > From: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] > On Behalf Of Jens Alfke > Sent: Friday, 3 March, 2017 17:19 > To: SQLite mailing list > Subject: Re: [sqlite] Massively multithreaded SQLite queries > > > > On Mar 3, 2017, at 3:51 PM, Simon Slavin <slav...@bigfraud.org> wrote: > > > > Then mess with the '5' until you find a good value. > > A common rule of thumb with thread pools is to allocate one thread per CPU > core. > > —Jens > _______________________________________________ > sqlite-users mailing list > sqlite-users@mailinglists.sqlite.org > https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmailinglists.sqlite.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsqlite-users&data=01%7C01%7Candrew.brown%40economicmodeling.com%7Ca4729ccfb1754b9a534008d46298b2d9%7C7cc1677566a34e8b80fd5b1f1db15061%7C0&sdata=C6yNkbM7p0uoib5OgXXYS7%2BEy8cJR1I6N8JjaQ4iMCU%3D&reserved=0 _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmailinglists.sqlite.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsqlite-users&data=01%7C01%7Candrew.brown%40economicmodeling.com%7Ca4729ccfb1754b9a534008d46298b2d9%7C7cc1677566a34e8b80fd5b1f1db15061%7C0&sdata=C6yNkbM7p0uoib5OgXXYS7%2BEy8cJR1I6N8JjaQ4iMCU%3D&reserved=0 _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
