{"action":"created","issue":{"url":"https://api.github.com/repos/BVLC/caffe/issues/2941","labels_url":"https://api.github.com/repos/BVLC/caffe/issues/2941/labels{/name}","comments_url":"https://api.github.com/repos/BVLC/caffe/issues/2941/comments","events_url":"https://api.github.com/repos/BVLC/caffe/issues/2941/events","html_url":"https://github.com/BVLC/caffe/pull/2941","id":101744151,"number":2941,"title":"Add some documentation on Multi-GPU support","user":{"login":"thatguymike","id":3503919,"avatar_url":"https://avatars.githubusercontent.com/u/3503919?v=3","gravatar_id":"","url":"https://api.github.com/users/thatguymike","html_url":"https://github.com/thatguymike","followers_url":"https://api.github.com/users/thatguymike/followers","following_url":"https://api.github.com/users/thatguymike/following{/other_user}","gists_url":"https://api.github.com/users/thatguymike/gists{/gist_id}","starred_url":"https://api.github.com/users/thatguymike/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/thatguymike/subscriptions","organizations_url":"https://api.github.com/users/thatguymike/orgs","repos_url":"https://api.github.com/users/thatguymike/repos","events_url":"https://api.github.com/users/thatguymike/events{/privacy}","received_events_url":"https://api.github.com/users/thatguymike/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/BVLC/caffe/labels/documentation","name":"documentation","color":"009800"},{"url":"https://api.github.com/repos/BVLC/caffe/labels/ready%20for%20review","name":"ready for review","color":"bfe5bf"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":4,"created_at":"2015-08-18T20:42:13Z","updated_at":"2015-08-18T22:58:52Z","closed_at":null,"pull_request":{"url":"https://api.github.com/repos/BVLC/caffe/pulls/2941","html_url":"https://github.com/BVLC/caffe/pull/2941","diff_url":"https://github.com/BVLC/caffe/pull/2941.diff","patch_url":"https://github.com/BVLC/caffe/pull/2941.patch"},"body":"Add initial documentation on Multi-GPU support.  "},"comment":{"url":"https://api.github.com/repos/BVLC/caffe/issues/comments/132385128","html_url":"https://github.com/BVLC/caffe/pull/2941#issuecomment-132385128","issue_url":"https://api.github.com/repos/BVLC/caffe/issues/2941","id":132385128,"user":{"login":"thatguymike","id":3503919,"avatar_url":"https://avatars.githubusercontent.com/u/3503919?v=3","gravatar_id":"","url":"https://api.github.com/users/thatguymike","html_url":"https://github.com/thatguymike","followers_url":"https://api.github.com/users/thatguymike/followers","following_url":"https://api.github.com/users/thatguymike/following{/other_user}","gists_url":"https://api.github.com/users/thatguymike/gists{/gist_id}","starred_url":"https://api.github.com/users/thatguymike/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/thatguymike/subscriptions","organizations_url":"https://api.github.com/users/thatguymike/orgs","repos_url":"https://api.github.com/users/thatguymike/repos","events_url":"https://api.github.com/users/thatguymike/events{/privacy}","received_events_url":"https://api.github.com/users/thatguymike/received_events","type":"User","site_admin":false},"created_at":"2015-08-18T22:58:52Z","updated_at":"2015-08-18T22:58:52Z","body":"Those that start with P should be okay in the case above (352 drivers).  Basically you want things connected via PCIe bridges or switches.  Do note that each bridge can increase latency and reduce BW.  There is no general tool available to show you all the connections in a usable way.  lspci -tv gets pretty close to show the PCIe bridge topology.\r\n\r\nFor example, from a DIGITS DevBox:\r\n\r\n            +-02.0-[07-0a]----00.0-[08-0a]--+-08.0-[0a]--+-00.0  NVIDIA Corporation Device 17c2\r\n             |                               |            \\-00.1  NVIDIA Corporation Device 0fb0\r\n             |                               \\-10.0-[09]--+-00.0  NVIDIA Corporation Device 17c2\r\n             |                                            \\-00.1  NVIDIA Corporation Device 0fb0\r\n             +-03.0-[03-06]----00.0-[04-06]--+-08.0-[06]--+-00.0  NVIDIA Corporation Device 17c2\r\n             |                               |            \\-00.1  NVIDIA Corporation Device 0fb0\r\n             |                               \\-10.0-[05]--+-00.0  NVIDIA Corporation Device 17c2\r\n             |                                            \\-00.1  NVIDIA Corporation Device 0fb0\r\n\r\nID 17c2 are the computing devices in my case (the other is the HDMI audio).  It shows there is a PLX bridge connecting 2 TitanX's to an x16 link to the CPU."}}