{"action":"created","issue":{"url":"https://api.github.com/repos/JuliaComputing/ArrayFire.jl/issues/12","repository_url":"https://api.github.com/repos/JuliaComputing/ArrayFire.jl","labels_url":"https://api.github.com/repos/JuliaComputing/ArrayFire.jl/issues/12/labels{/name}","comments_url":"https://api.github.com/repos/JuliaComputing/ArrayFire.jl/issues/12/comments","events_url":"https://api.github.com/repos/JuliaComputing/ArrayFire.jl/issues/12/events","html_url":"https://github.com/JuliaComputing/ArrayFire.jl/issues/12","id":133157324,"number":12,"title":"Linear Algebra routines are slow","user":{"login":"ranjanan","id":9101377,"avatar_url":"https://avatars.githubusercontent.com/u/9101377?v=3","gravatar_id":"","url":"https://api.github.com/users/ranjanan","html_url":"https://github.com/ranjanan","followers_url":"https://api.github.com/users/ranjanan/followers","following_url":"https://api.github.com/users/ranjanan/following{/other_user}","gists_url":"https://api.github.com/users/ranjanan/gists{/gist_id}","starred_url":"https://api.github.com/users/ranjanan/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/ranjanan/subscriptions","organizations_url":"https://api.github.com/users/ranjanan/orgs","repos_url":"https://api.github.com/users/ranjanan/repos","events_url":"https://api.github.com/users/ranjanan/events{/privacy}","received_events_url":"https://api.github.com/users/ranjanan/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"assignees":[],"milestone":null,"comments":14,"created_at":"2016-02-12T04:48:47Z","updated_at":"2016-07-12T22:18:46Z","closed_at":null,"body":"Some linear algebra routines are slow on ArrayFire. \r\n```julia\r\na = rand(1000, 1000) #Generate double precision random values\r\nad = AFArray(a) #Transfer to GPU\r\n@time svd(a); # CPU\r\n0.487003 seconds (43 allocations: 53.529 MB, 0.69% gc time)\r\n@time svd(ad); # GPU\r\n5.481788 seconds (14 allocations: 336 bytes)\r\n@time lu(a); #CPU\r\n0.023986 seconds (38 allocations: 22.905 MB, 14.06% gc time)\r\n@time lu(ad); # GPU\r\n0.057869 seconds (17 allocations: 384 bytes)\r\n@time qr(a); # CPU\r\n0.113873 seconds (46 allocations: 31.068 MB, 2.55% gc time)\r\n@time qr(ad); #GPU\r\n0.891739 seconds (14 allocations: 336 bytes)\r\n```\r\n"},"comment":{"url":"https://api.github.com/repos/JuliaComputing/ArrayFire.jl/issues/comments/232199294","html_url":"https://github.com/JuliaComputing/ArrayFire.jl/issues/12#issuecomment-232199294","issue_url":"https://api.github.com/repos/JuliaComputing/ArrayFire.jl/issues/12","id":232199294,"user":{"login":"davidavdav","id":5497303,"avatar_url":"https://avatars.githubusercontent.com/u/5497303?v=3","gravatar_id":"","url":"https://api.github.com/users/davidavdav","html_url":"https://github.com/davidavdav","followers_url":"https://api.github.com/users/davidavdav/followers","following_url":"https://api.github.com/users/davidavdav/following{/other_user}","gists_url":"https://api.github.com/users/davidavdav/gists{/gist_id}","starred_url":"https://api.github.com/users/davidavdav/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/davidavdav/subscriptions","organizations_url":"https://api.github.com/users/davidavdav/orgs","repos_url":"https://api.github.com/users/davidavdav/repos","events_url":"https://api.github.com/users/davidavdav/events{/privacy}","received_events_url":"https://api.github.com/users/davidavdav/received_events","type":"User","site_admin":false},"created_at":"2016-07-12T22:18:46Z","updated_at":"2016-07-12T22:18:46Z","body":"I have trouble showing any performance using ArrayFire on a new but consumer nvidia gtx 1080 in Float32, for things as simple as a matrix multiplication.  For a test function like\r\n```\r\nfunction ata(a, n) \r\n       for i=1:n \r\n           b=a'a\r\n       end\r\n       sync()\r\n end\r\n```\r\nthe cpu is in my test several times faster than the GPU, for various matrix sizes for `a`  and `n`. \r\n"}}
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