Hadoop 2 (YARN) default configuration values

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Where to check the default Hadoop 2 (YARN) configuration values for: HDFS: hdfs-site.xml YARN: yarn-site.xml MapReduce: mapred-site.xml Default Hadoop 2 (YARN) configuration values for Hadoop 2.2.0 from Apache Hadoop website: HDFS: http://hadoop.apache.org/docs/r2.2.0/hadoop-project-dist/hadoop-hdfs/hdfs-default.xml YARN: https://hadoop.apache.org/docs/r2.2.0/hadoop-yarn/hadoop-yarn-common/yarn-default.xml MapReduce: https://hadoop.apache.org/docs/r2.2.0/hadoop-mapreduce-client/hadoop-mapreduce-client-core/mapred-default.xml

How to back up a complete IMAP account?

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I have a large IMAP email account which contains many emails in a rich structure of directories. How to back up the whole IMAP account to my local computer? The requirements: Automatically downloading these files. There are many directories, and copying-pasting emails will take too much time. Keep the directory structures which are used to
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How to make xterm display Chinese characters?

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How to make xterm display Chinese characters? It just displays some small rectangles for Chinese characters. First, the settings for some old X programs like xterm is in ~/.Xresources. And it takes effect after the X server restarts, or you can manually load the settings by xrdb -merge ~/.Xresources Second, the Chinese or similar fonts
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How to change the window title font family and size in Gnome 3?

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It was ever possible to set it in gnome-teak-tool. However, in the latest Gnome 3, it disappears. Is there any other way to set it? The configuration is the org.gnome.desktop.wm.preferences titlebar-font under dconf. You can use dconf-editor to find the appropriate key entry and set it. Or use gsettings: $ gsettings set org.gnome.desktop.wm.preferences titlebar-font ‘Sans
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How to use different keys for different git servers?

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I have access to different git servers. I have several keys for these servers. How to use different keys for different git servers? Use the .ssh/config file to specify different configuration for different SSH servers used by git: For example: Host git.example.org Port 22111 IdentityFile ~/.ssh/id_rsa.git.example.org Host code.example.org Port 22 IdentityFile ~/.ssh/id_rsa.code.example.org which specifies the
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Xen HVM DomU configuration file

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An example of Xen HVM DomU configuration file. An example for install the OS from an ISO: name=”10.0.1.235″ vcpus=2 memory=2048 shadow_memory=8 disk=[‘file:/lhome/xen/vm-10.0.1.235/vmdisk0,xvda,w’, ‘file:/lhome/Linux-x86_64-DVD.iso,xvdc:cdrom,r’] vif=[‘bridge=xenbr0′] kernel=’/usr/lib/xen/boot/hvmloader’ builder=’hvm’ device_model=’/usr/lib64/xen/bin/qemu-dm’ extra=” vnc=1 vnclisten=”0.0.0.0″ vncpasswd=’1234567′ # vncdisplay=1 vncconsole=1 on_reboot=’restart’ on_crash=’restart’ An example for run the VM after installation: name=”10.0.1.235″ vcpus=2 memory=2048 shadow_memory=8 disk=[‘file:/lhome/xen/vm-10.0.1.235/vmdisk0,xvda,w’] vif=[‘bridge=xenbr0′] kernel=’/usr/lib/xen/boot/hvmloader’ builder=’hvm’ device_model=’/usr/lib64/xen/bin/qemu-dm’ extra=” vnc=1
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How to find out and change the storage engine of tables in MySQL

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How to find out and change the storage engine of tables in MySQL databases? Find out the storage engine of a table in a database: SELECT ENGINE FROM information_schema.TABLES WHERE TABLE_SCHEMA = ‘database’ AND TABLE_NAME = ‘table’ Change the storage engine of a table: ALTER TABLE table ENGINE = type type can be innodb or
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How to change the maximum execution time and memory size allowed for PHP

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I see this message in the error log of httpd: PHP Fatal error: Maximum execution time of 30 seconds exceeded in and PHP Fatal error: Allowed memory size of 268435456 bytes exhausted How to change them to a longer and larger value? To change the allowed maximum memory usage of PHP: Set memory_limit = 256M
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Question2answer: show excerpt in the RSS feed

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There is a “Include full text in feeds:” option in the “RSS feeds” configuration panel but no options/method to only show excerpt instead of the “full text” or nothing for RSS feeds. This need to hack the question2answer source code. Details are in the answer. The changes based on Question2asnwer 1.5.4: diff –git a/qa-include/qa-index.php b/qa-include/qa-index.php
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How to delete all topics and posts from a user/spammer in myBB?

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This is a tutorial on “how to delete all topics and posts from a user/spammer in myBB”. Please check out the answer. I use the Goodbye Spammer plugin for MyBB. First, install it after downloading the plugin form its homepage: Upload ./inc/plugins/goodbyespammer.php to ./inc/plugins/ Upload ./inc/languages/english/goodbyespammer.lang.php to ./inc/languages/english/ Go to ACP > Plugins > Activate
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Where are the Linux routing table entries stored on disk?

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I know the routing tables on Linux is in memory after being set. However, where are the routing table entries stored on disk? I mean where are the routing table is persistently stored so that the routing table can be reloaded like the iptables (under /etc/sysconfig/iptables on Fedora/RHEL/CentOS Linuxes). If the system uses the /etc/rc.d/init.d/network
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How to use OCaml as a script language?

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How to use OCaml as a script language like bash and python? It will be good that I can write a script in OCaml and directly invoke it. For example, I write a script named “script.ml” and then I can invoke it directly by $ ./script.ml Thanks! Three helloworld scripts: script3.ml #! /usr/bin/env ocaml print_string
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Chrome’s KDE proxy integration broken on KDE / Fedora

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Chrome reads the proxy settings from Gnome correctly. However, when I run Chrome under KDE, the proxy integration is broken: In the settings of Chrome, clicking the “Change proxy settings” opens the KDE proxy setting dialog correctly (the command kcmshell4 proxy actually is executed). However, after the proxy settings are made, Chrome does not read
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Make changes to sysctl.conf take effect without rebooting Linux?

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I made some changes to /etc/sysctl.conf. I know it will take effect next time Linux boots. However, how to make the changes to sysctl.conf take effect without rebooting Linux? You can force Linux to reload the new configuration in /etc/sysctl.conf by: execute the following command as root: sysctl -p For more details, check the manual
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Squeezing Space in LaTeX – SysTutorials QA

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How to squeeze space in Latex? A good tutorial about “squeezing space in LaTex” in here from the Cambridge University’s website: http://www.eng.cam.ac.uk/help/tpl/textprocessing/squeeze.html These settings work great for me: setlength{textfloatsep}{1pt} setlength{abovecaptionskip}{1pt} setlength{belowcaptionskip}{1pt} A more aggressive configuration to squeeze space in a LaTex doc: % save space usepackage{enumitem} setlist{nolistsep} % no space between refs usepackage{bibspacing} setlength{bibspacing}{baselineskip} usepackage[small,compact]{titlesec}
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Adding custom buttons to the WordPress HTML Editor

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However, there is only limited buttons in the default WordPress HTML editor. How to custom the HTML editor buttions? I like HTML editors with BBCode in WordPress and totally disable the Visual Editor. However, there is only limited buttons in the default WordPress HTML editor. I found a plugin to custom the HTML editor buttions.
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Where Does Evolution Save Its Data and Configuration Files on Linux?

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Evolution is a great personal information management tool that provides Email, address book and calendar tools. Evolution provides many enterprise friendly feature such as native support to Microsoft Exchange connectivity for Emails, address books and calendars. Evolution uses various ways including plain files and dconf configuration systems. This post will give an introduction to the
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How to Export an NFSv4 Server to External Networks

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We ever discussed fixing ports used by NFSv3 so that it can be easily exported to external networks. For NFSv4.1 or higher, things are much easier. The ports for mountd, statd, and lockd are not required in a pure NFSv4 environment. We have less ports to control or allow for connections. Only port 111 and
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