August 2015
Intermediate to advanced
312 pages
7h 28m
Japanese
Content preview from 初めてのSpark
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
277
C.6 検証結果
C-3
ー
C.6
実行時間を測定した結果、アイテムベースでは、
Spark
は
MapReduce
の約
5
分の
1
、
ALS
では
約
32
分の
1
という結果となりました。詳細な結果を、
C-4
および
C-4
、
C-5
に示します。
ALS
は繰り返し処理が多いため
Spark
と
MapReduce
の実行速度の違いが顕著に示されました。
今回の検証では、
ALS
の繰り返し回数を
10
で測定しましたが、繰り返し回数が多ければ、実行時
間の差はさらに大きくなるでしょう。また、逐次的なアイテムベースでも約
5
倍の実行速度が得
られたことも、注目に値する結果です。
C-4
ALS
No.
ー
Spark
Mahout
(Mahout/Spark)
1 21,988,008 00:02:17 00:21:29 9.4
2 35,872,326 00:03:14 00:36:48 11.4
3 61,192,747 00:04:20 01:07:55 15.7
4 77,865,758 00:04:28 01:37:44 21.9
5 97,967,251 00:05:35 02:17:24 24.6
6 116,938,309 00:06:32 02:52:28 26.4
7 134,976,806 00:06:55 03:41:46 32.1
データ量20日
データ量40日
①分割過少
②分割過多
1,200
1,000
800
600
400 ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.