{"action":"created","issue":{"url":"https://api.github.com/repos/druid-io/druid/issues/2084","labels_url":"https://api.github.com/repos/druid-io/druid/issues/2084/labels{/name}","comments_url":"https://api.github.com/repos/druid-io/druid/issues/2084/comments","events_url":"https://api.github.com/repos/druid-io/druid/issues/2084/events","html_url":"https://github.com/druid-io/druid/pull/2084","id":121651835,"number":2084,"title":"minor optimize IndexMerger's MMappedIndexRowIterable","user":{"login":"binlijin","id":1531353,"avatar_url":"https://avatars.githubusercontent.com/u/1531353?v=3","gravatar_id":"","url":"https://api.github.com/users/binlijin","html_url":"https://github.com/binlijin","followers_url":"https://api.github.com/users/binlijin/followers","following_url":"https://api.github.com/users/binlijin/following{/other_user}","gists_url":"https://api.github.com/users/binlijin/gists{/gist_id}","starred_url":"https://api.github.com/users/binlijin/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/binlijin/subscriptions","organizations_url":"https://api.github.com/users/binlijin/orgs","repos_url":"https://api.github.com/users/binlijin/repos","events_url":"https://api.github.com/users/binlijin/events{/privacy}","received_events_url":"https://api.github.com/users/binlijin/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":10,"created_at":"2015-12-11T07:06:58Z","updated_at":"2015-12-15T06:50:58Z","closed_at":null,"pull_request":{"url":"https://api.github.com/repos/druid-io/druid/pulls/2084","html_url":"https://github.com/druid-io/druid/pull/2084","diff_url":"https://github.com/druid-io/druid/pull/2084.diff","patch_url":"https://github.com/druid-io/druid/pull/2084.patch"},"body":"Copy from IndexMaker."},"comment":{"url":"https://api.github.com/repos/druid-io/druid/issues/comments/164661736","html_url":"https://github.com/druid-io/druid/pull/2084#issuecomment-164661736","issue_url":"https://api.github.com/repos/druid-io/druid/issues/2084","id":164661736,"user":{"login":"binlijin","id":1531353,"avatar_url":"https://avatars.githubusercontent.com/u/1531353?v=3","gravatar_id":"","url":"https://api.github.com/users/binlijin","html_url":"https://github.com/binlijin","followers_url":"https://api.github.com/users/binlijin/followers","following_url":"https://api.github.com/users/binlijin/following{/other_user}","gists_url":"https://api.github.com/users/binlijin/gists{/gist_id}","starred_url":"https://api.github.com/users/binlijin/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/binlijin/subscriptions","organizations_url":"https://api.github.com/users/binlijin/orgs","repos_url":"https://api.github.com/users/binlijin/repos","events_url":"https://api.github.com/users/binlijin/events{/privacy}","received_events_url":"https://api.github.com/users/binlijin/received_events","type":"User","site_admin":false},"created_at":"2015-12-15T06:50:58Z","updated_at":"2015-12-15T06:50:58Z","body":"I test it on our test machine, the performance number is：\r\nBefore：\r\n2015-12-15 06:29:47,050 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base8567491474144566728flush/merged/v8-tmp] walked 500,000/500,000 rows in 21,429 millis.\r\n2015-12-15 06:30:11,859 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base8567491474144566728flush/merged/v8-tmp] completed walk through of 916,822 rows in 46,276 millis.\r\n\r\n2015-12-15 06:35:17,978 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base8564891586222722664flush/merged/v8-tmp] walked 500,000/500,000 rows in 22,278 millis.\r\n2015-12-15 06:35:43,443 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base8564891586222722664flush/merged/v8-tmp] completed walk through of 916,822 rows in 47,780 millis.\r\n\r\n2015-12-15 06:37:38,199 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base7286842343919247533flush/merged/v8-tmp] walked 500,000/500,000 rows in 21,865 millis.\r\n2015-12-15 06:38:01,388 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base7286842343919247533flush/merged/v8-tmp] completed walk through of 916,822 rows in 45,092 millis.\r\n\r\nAfter：\r\n2015-12-15 06:08:30,580 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base7086414238284544897flush/merged/v8-tmp] walked 500,000/500,000 rows in 20,996 millis.\r\n2015-12-15 06:08:55,490 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base7086414238284544897flush/merged/v8-tmp] completed walk through of 916,822 rows in 45,943 millis.\r\n\r\n2015-12-15 06:10:55,844 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base3754891995514154122flush/merged/v8-tmp] walked 500,000/500,000 rows in 19,548 millis.\r\n2015-12-15 06:11:20,352 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base3754891995514154122flush/merged/v8-tmp] completed walk through of 916,822 rows in 44,095 millis.\r\n\r\n2015-12-15 06:13:21,332 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base2471600163749106438flush/merged/v8-tmp] walked 500,000/500,000 rows in 21,338 millis.\r\n2015-12-15 06:13:45,834 INFO  [main] segment.IndexMerger (Logger.java:info(70)) - outDir[/tmp/base2471600163749106438flush/merged/v8-tmp] completed walk through of 916,822 rows in 45,878 millis.\r\n\r\nIt is slow because my laptop is SSD and this machine is not.\r\n\r\nprocessor\t: 23\r\nvendor_id\t: GenuineIntel\r\ncpu family\t: 6\r\nmodel\t\t: 45\r\nmodel name\t: Intel(R) Xeon(R) CPU E5-2430 0 @ 2.20GHz\r\nstepping\t: 7\r\ncpu MHz\t\t: 2194.333\r\ncache size\t: 15360 KB\r\nphysical id\t: 1\r\nsiblings\t: 12\r\ncore id\t\t: 5\r\ncpu cores\t: 6\r\napicid\t\t: 43\r\ninitial apicid\t: 43\r\nfpu\t\t: yes\r\nfpu_exception\t: yes\r\ncpuid level\t: 13\r\nwp\t\t: yes\r\n"}}