{"action":"created","issue":{"url":"https://api.github.com/repos/chapel-lang/chapel/issues/2849","labels_url":"https://api.github.com/repos/chapel-lang/chapel/issues/2849/labels{/name}","comments_url":"https://api.github.com/repos/chapel-lang/chapel/issues/2849/comments","events_url":"https://api.github.com/repos/chapel-lang/chapel/issues/2849/events","html_url":"https://github.com/chapel-lang/chapel/pull/2849","id":114158924,"number":2849,"title":"Default to qthreads+hwloc for KNC instead of fifo","user":{"login":"ronawho","id":1588337,"avatar_url":"https://avatars.githubusercontent.com/u/1588337?v=3","gravatar_id":"","url":"https://api.github.com/users/ronawho","html_url":"https://github.com/ronawho","followers_url":"https://api.github.com/users/ronawho/followers","following_url":"https://api.github.com/users/ronawho/following{/other_user}","gists_url":"https://api.github.com/users/ronawho/gists{/gist_id}","starred_url":"https://api.github.com/users/ronawho/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/ronawho/subscriptions","organizations_url":"https://api.github.com/users/ronawho/orgs","repos_url":"https://api.github.com/users/ronawho/repos","events_url":"https://api.github.com/users/ronawho/events{/privacy}","received_events_url":"https://api.github.com/users/ronawho/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":8,"created_at":"2015-10-29T22:15:04Z","updated_at":"2015-11-09T23:23:58Z","closed_at":null,"pull_request":{"url":"https://api.github.com/repos/chapel-lang/chapel/pulls/2849","html_url":"https://github.com/chapel-lang/chapel/pull/2849","diff_url":"https://github.com/chapel-lang/chapel/pull/2849.diff","patch_url":"https://github.com/chapel-lang/chapel/pull/2849.patch"},"body":"When we originally added support for KNC we saw poor performance with qthreads.\r\nHowever, this was before we did any performance tuning with qthreads. In\r\nparticular we were using a work stealing scheduler, which did not perform well\r\nespecially as more cores were added.\r\n\r\nMotivated by some recent work with stream and hwloc I decided to see if the\r\nperformance with qthreads is better now. The short summary is that\r\nqthreads+hwloc performance is better, at least for stream (121 vs 115 GB/s.) As\r\na next step I'd like to add some nightly performance testing for KNC.\r\n\r\nIn the past hwloc didn't build on stream, but it appears to build just fine\r\nnow. This patch adds code to throw `-mmic` for KNC builds in the hwloc Makefile\r\njust like we do for our other third-party libraries.\r\n\r\nThe specific changes in this patch are:\r\n - make qthreads and hwloc the defaults in the chplenv scripts\r\n - throw `-mmic` for KNC builds in hwloc Makefile\r\n - update documentation that mentioned fifo as the tasking layer for KNC"},"comment":{"url":"https://api.github.com/repos/chapel-lang/chapel/issues/comments/155231160","html_url":"https://github.com/chapel-lang/chapel/pull/2849#issuecomment-155231160","issue_url":"https://api.github.com/repos/chapel-lang/chapel/issues/2849","id":155231160,"user":{"login":"ronawho","id":1588337,"avatar_url":"https://avatars.githubusercontent.com/u/1588337?v=3","gravatar_id":"","url":"https://api.github.com/users/ronawho","html_url":"https://github.com/ronawho","followers_url":"https://api.github.com/users/ronawho/followers","following_url":"https://api.github.com/users/ronawho/following{/other_user}","gists_url":"https://api.github.com/users/ronawho/gists{/gist_id}","starred_url":"https://api.github.com/users/ronawho/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/ronawho/subscriptions","organizations_url":"https://api.github.com/users/ronawho/orgs","repos_url":"https://api.github.com/users/ronawho/repos","events_url":"https://api.github.com/users/ronawho/events{/privacy}","received_events_url":"https://api.github.com/users/ronawho/received_events","type":"User","site_admin":false},"created_at":"2015-11-09T23:23:58Z","updated_at":"2015-11-09T23:23:58Z","body":"Just copying the failures here, because I keep losing which configs are actually failing:\r\n\r\n```\r\n[Error: Timed out executing program release/examples/benchmarks/lulesh/lulesh (compopts: 1, execopts: 4)]\r\n[Error: Timed out executing program release/examples/benchmarks/lulesh/lulesh (compopts: 1, execopts: 5)]\r\n[Error: Timed out executing program release/examples/benchmarks/lulesh/lulesh (compopts: 2, execopts: 4)]\r\n[Error: Timed out executing program release/examples/benchmarks/lulesh/lulesh (compopts: 2, execopts: 5)]\r\n[Error: Timed out executing program release/examples/benchmarks/miniMD/miniMD (compopts: 1)]\r\n[Error: Timed out executing program release/examples/benchmarks/miniMD/miniMD (compopts: 2)]\r\n[Error: Timed out executing program release/examples/benchmarks/miniMD/explicit/miniMD]\r\n\r\n```"}}