How to set the number of mappers and reducers of Hadoop in command line?

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How to set the number of mappers and reducers of Hadoop in command line? Number of mappers and reducers can be set like (5 mappers, 2 reducers): -D mapred.map.tasks=5 -D mapred.reduce.tasks=2 in the command line. In the code, one can configure JobConf variables. job.setNumMapTasks(5); // 5 mappers job.setNumReduceTasks(2); // 2 reducers Note that on Hadoop
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How to import a googlecode git project to github project

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I wanna migrate leveldb (code.google.com/p/leveldb) to my github repository. Create a new repo on github.com with this link https://help.github.com/articles/creating-a-new-repository git clone https://code.google.com/p/ project-name.git Set the remote origin url as follows: git remote set-url origin https://github.com/ username/ repo-name.git git pull to pull the latest. git push origin master after making local changes. This is the original
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How to adjust the system partition (C:) size of Windows?

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The disk management tools of Windows can adjust it to some level. But there are more space available as far as I can tell. How to further adjust the system partition (C:) size of Windows? You may check these tools: EASEUS Partition Master (free) Includes Partition Manager, Disk & Partition Copy Wizard and Partition Recovery
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x86-64 instructions for floating-point comparisons

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What are the x86-64 instructions for floating-point comparisons like the cmpq for quard-word integer comparison? The SSE3 extenstions provide two instructions for comparing floating values: Instruction Based on Description ucomiss S2, S1 S1 – S2 Compare single precision ucomisd S2, S1 S1 – S2 Compare double precision As with cmpq, they follow the GAS convention
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Fix the Grub issue with Windows 8 UEFI after installing Fedora 20

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Grub fails to boot with Windows 8 UEFI after installing Fedora 20. The Grub entry for Windows 8 is: menuentry ‘Windows Boot Manager’ { chainloader /EFI/Microsoft/Boot/bootmgfw.efi boot } How to fix it? The set root= is missing. You probably can fix this by specifying the root manually: menuentry ‘Windows Boot Manager’ { insmod part_gpt set
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How to download a youtube video to my computer?

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How to download a youtube video to my computer? You may use the ClipConverter.cc for downloading Youtube videos: http://www.clipconverter.cc/ How to download a YouTube video: Paste your YouTube URL at ‘Media URL’ and press Continue. Select the format and the options for the conversion. The default options are for most videos a good setting. Press
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Enlarging Linux UDP buffer size

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One of the most common causes of UDP data gram lost on Linux is an undersized receive buffer on the Linux socket. How to enlarge Linux UDP buffer size? On Linux, you can change the UDP buffer size (e.g. to 26214400) by (as root): sysctl -w net.core.rmem_max=26214400 The default buffer size on Linux is 131071.
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Filter away non-printable ASCII characters on Linux?

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Sometimes the commands’ output have some non-printable ASCII characters. How to filter away these non-printable ASCII characters on Linux? You can consider the problem as “how to leave only printable ascii characters?”. The printable characters in ASCII table are: Octal 011: Tab Octal 012: Line Feed Octal 015: Carriage Return Octal 040 to 176: printable
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