{"action":"created","issue":{"url":"https://api.github.com/repos/OPM/opm-material/issues/144","repository_url":"https://api.github.com/repos/OPM/opm-material","labels_url":"https://api.github.com/repos/OPM/opm-material/issues/144/labels{/name}","comments_url":"https://api.github.com/repos/OPM/opm-material/issues/144/comments","events_url":"https://api.github.com/repos/OPM/opm-material/issues/144/events","html_url":"https://github.com/OPM/opm-material/pull/144","id":149800791,"number":144,"title":"Tabulation classes: some micro-optimizations w.r.t. Evaluations","user":{"login":"andlaus","id":1837735,"avatar_url":"https://avatars.githubusercontent.com/u/1837735?v=3","gravatar_id":"","url":"https://api.github.com/users/andlaus","html_url":"https://github.com/andlaus","followers_url":"https://api.github.com/users/andlaus/followers","following_url":"https://api.github.com/users/andlaus/following{/other_user}","gists_url":"https://api.github.com/users/andlaus/gists{/gist_id}","starred_url":"https://api.github.com/users/andlaus/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/andlaus/subscriptions","organizations_url":"https://api.github.com/users/andlaus/orgs","repos_url":"https://api.github.com/users/andlaus/repos","events_url":"https://api.github.com/users/andlaus/events{/privacy}","received_events_url":"https://api.github.com/users/andlaus/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":11,"created_at":"2016-04-20T15:18:40Z","updated_at":"2016-04-29T19:37:34Z","closed_at":null,"pull_request":{"url":"https://api.github.com/repos/OPM/opm-material/pulls/144","html_url":"https://github.com/OPM/opm-material/pull/144","diff_url":"https://github.com/OPM/opm-material/pull/144.diff","patch_url":"https://github.com/OPM/opm-material/pull/144.patch"},"body":"with this, some relatively expensive \"Evaluation times Scalar\" multiplications are replaced by relatively cheap \"Scalar times Scalar\" ones.\r\n\r\nalthough this changes convergence behavior of flow for norne slightly, I could not find any effect on the results and performance was also negatively affected:\r\n\r\nbefore:\r\n\r\n```\r\nTotal time taken (seconds):  1301.86\r\nSolver time (seconds):       1298.17\r\nOverall Newton Iterations:   1625\r\nOverall Linear Iterations:   25233\r\n```\r\n\r\nafter:\r\n\r\n```\r\nTotal time taken (seconds):  1254.06\r\nSolver time (seconds):       1250.26\r\nOverall Newton Iterations:   1626\r\nOverall Linear Iterations:   24950\r\n```\r\n\r\nalso note that -- since the corresponding release branch has already been created for opm-material -- this patch is not going to be part of the impeding OPM-2016.04 release unless explicitly requested otherwise."},"comment":{"url":"https://api.github.com/repos/OPM/opm-material/issues/comments/215857526","html_url":"https://github.com/OPM/opm-material/pull/144#issuecomment-215857526","issue_url":"https://api.github.com/repos/OPM/opm-material/issues/144","id":215857526,"user":{"login":"andlaus","id":1837735,"avatar_url":"https://avatars.githubusercontent.com/u/1837735?v=3","gravatar_id":"","url":"https://api.github.com/users/andlaus","html_url":"https://github.com/andlaus","followers_url":"https://api.github.com/users/andlaus/followers","following_url":"https://api.github.com/users/andlaus/following{/other_user}","gists_url":"https://api.github.com/users/andlaus/gists{/gist_id}","starred_url":"https://api.github.com/users/andlaus/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/andlaus/subscriptions","organizations_url":"https://api.github.com/users/andlaus/orgs","repos_url":"https://api.github.com/users/andlaus/repos","events_url":"https://api.github.com/users/andlaus/events{/privacy}","received_events_url":"https://api.github.com/users/andlaus/received_events","type":"User","site_admin":false},"created_at":"2016-04-29T19:37:34Z","updated_at":"2016-04-29T19:37:34Z","body":"> A 5% increase in Newton iterations for such a small change is alarming. \r\n\r\nadd that to the fact that mathematically nothing should have changed. (if there's no major gotcha in this patch of course.) The only thing which *did* change is the order of operations which are supposed to be commutative.\r\n\r\nto me it seems like there's something really fishy going on here. maybe the precision of the linear solver is too low?"}}