{"action":"created","issue":{"url":"https://api.github.com/repos/xianyi/OpenBLAS/issues/844","repository_url":"https://api.github.com/repos/xianyi/OpenBLAS","labels_url":"https://api.github.com/repos/xianyi/OpenBLAS/issues/844/labels{/name}","comments_url":"https://api.github.com/repos/xianyi/OpenBLAS/issues/844/comments","events_url":"https://api.github.com/repos/xianyi/OpenBLAS/issues/844/events","html_url":"https://github.com/xianyi/OpenBLAS/issues/844","id":149717449,"number":844,"title":"DPOTRF deadlocks on arm cortex A15","user":{"login":"emilienkofman","id":551186,"avatar_url":"https://avatars.githubusercontent.com/u/551186?v=3","gravatar_id":"","url":"https://api.github.com/users/emilienkofman","html_url":"https://github.com/emilienkofman","followers_url":"https://api.github.com/users/emilienkofman/followers","following_url":"https://api.github.com/users/emilienkofman/following{/other_user}","gists_url":"https://api.github.com/users/emilienkofman/gists{/gist_id}","starred_url":"https://api.github.com/users/emilienkofman/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/emilienkofman/subscriptions","organizations_url":"https://api.github.com/users/emilienkofman/orgs","repos_url":"https://api.github.com/users/emilienkofman/repos","events_url":"https://api.github.com/users/emilienkofman/events{/privacy}","received_events_url":"https://api.github.com/users/emilienkofman/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":3,"created_at":"2016-04-20T09:45:12Z","updated_at":"2016-04-21T09:17:35Z","closed_at":null,"body":"Using the benchmarks I noticed that the potrf kernel would deadlock on my A15 arm board (odroid):\r\n\r\n```\r\n$ OPBLAS_NUM_THREADS=2 ./dpotrf.goto \r\nFrom :   1  To : 200 Step =   1 Uplo = U\r\n       1 :       0.01 MFlops :      0.000 Sec : Test=F\r\n       2 :       0.07 MFlops :      0.000 Sec : Test=F\r\n       3 :       0.25 MFlops :      0.000 Sec : Test=F\r\n       4 :       0.59 MFlops :      0.000 Sec : Test=F\r\n       5 :       0.90 MFlops :      0.000 Sec : Test=F\r\n       6 :       1.57 MFlops :      0.000 Sec : Test=F\r\n       7 :       2.59 MFlops :      0.000 Sec : Test=F\r\n       8 :       3.92 MFlops :      0.000 Sec : Test=F\r\n\r\n```\r\nand then it stalls. On contrary running it with `OPENBLAS_NUM_THREADS=1` is fine.\r\n\r\nI used the latest version of the code forked from here, gcc 5.2.1, the board runs Ubuntu 15.10 and here is some more information:\r\n```\r\n$ uname -a\r\nLinux odroid 3.10.96+ #1 SMP PREEMPT Wed Mar 30 11:47:52 UTC 2016 armv7l armv7l armv7l GNU/Linux\r\n```\r\nPlease tell me if I can add any other information that would make this reproducible. I don't know which difference in the setup causes the deadlock but on my laptop (Intel, 64bits, Debian), the multithreaded dpotrf runs just fine.\r\n\r\nI observed the same with the dcholesky benchmark, but I guess they just use the same routine."},"comment":{"url":"https://api.github.com/repos/xianyi/OpenBLAS/issues/comments/212825254","html_url":"https://github.com/xianyi/OpenBLAS/issues/844#issuecomment-212825254","issue_url":"https://api.github.com/repos/xianyi/OpenBLAS/issues/844","id":212825254,"user":{"login":"emilienkofman","id":551186,"avatar_url":"https://avatars.githubusercontent.com/u/551186?v=3","gravatar_id":"","url":"https://api.github.com/users/emilienkofman","html_url":"https://github.com/emilienkofman","followers_url":"https://api.github.com/users/emilienkofman/followers","following_url":"https://api.github.com/users/emilienkofman/following{/other_user}","gists_url":"https://api.github.com/users/emilienkofman/gists{/gist_id}","starred_url":"https://api.github.com/users/emilienkofman/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/emilienkofman/subscriptions","organizations_url":"https://api.github.com/users/emilienkofman/orgs","repos_url":"https://api.github.com/users/emilienkofman/repos","events_url":"https://api.github.com/users/emilienkofman/events{/privacy}","received_events_url":"https://api.github.com/users/emilienkofman/received_events","type":"User","site_admin":false},"created_at":"2016-04-21T09:17:35Z","updated_at":"2016-04-21T09:17:35Z","body":"Here is the full report: https://gist.github.com/emilienkofman/5c707c6af1eaddcf5587a0429de27ae2"}}