It is quite common to measure the time in programs using APIs like clock() and gettimeofday(). We may also want to measure the time “accurately” for certain purposes, such as measuring a small piece of code’s execution time for performance analysis, or measuring the time in time-sensitive game software. It is hard to measure the…
John Ousterhout is a professor of Deparment of Computer Science from Stanford University. One recent project he is working on is the RAMCloud, a “new class of storage, based entirely in DRAM, that is 2-3 orders of magnitude faster than existing storage systems”. He posts his “Favorite Sayings” on his homepage. These sayings are precious…
MediaWiki set’s the default page (the homepage) to the “Main Page” by default. The name “Main Page” is too general and does not give more meanings. Usually for a specific site, we may change it to some meaningful name and URL. This is a configurable in MediaWiki. This tutorial introduces how to change MediaWiki’s Main…
More and more users are browsing the Internet using a mobile device. It is preferred to provide good experience for these users. One method to service a mobile version of the page to a user with a mobile device. This tutorial introduces how to add mobile skin support for MediaWiki. Skin for mobile devices I…
MediaWiki is the wiki-engine that runs Wikipedia. In this tutorial, we introduce how to configure search engine friendly URLs in MediaWiki. ==Search Engine Friendly URLs== Default MediaWiki URLs look like www.example.com/w/index.php?title=TITLE which is a little ugly. To make it more search engine friendly, we will change it to SEO-friendly URLs like www.example.com/w/TITLE. ==Enabling Search Engine…
Make is a utility that automatically builds executable programs and libraries from source code by reading files called makefiles which specify how to derive the target program. Make is widely used, especially in Unix/Linux world. More introductions to Make and it’s history can be found on Wikipedia. In this post, I list articles for Makefile…
OCaml is an interesting functional language. There are lots learning materials on the Internet. I compile a list of resources for OCaml learning and reference. Recommended OCaml learning and reference material Online book of Real World OCaml by Yaron Minsky, Anil Madhavapeddy, Jason Hickey. A very good tutorial by Jason Hickey: http://www.cs.caltech.edu/courses/cs134/cs134b/book.pdf. The OCaml system…
The latest tools for upgrading Fedora is FedUp, please check How to upgrade Fedora 19 to Fedora 20 through the network. Please consider PreUpgrade for upgrading Fedora. This is the recommended method. This post makes a list of actions should be done to upgrade Fedora using yum. Please note that this is for experienced users…
I have done some I/O performance benchmark test of Xen DomU. For easier management, some of our DomU VMs are using file-backed VBDs. Previously, our VMs are using Loopback-mounted file-backed VBDs. But blktap-based support are recommended by Xen community. Before considering changing from loopback based VBD to blktap based VBD, I have done this performance…
After [[hadoop-installation-tutorial|installing Hadoop]], we usually run some benchmark programs to test whether the system works well. In the post of the Hadoop install tutorial, we show a very simple to grep strings from a simple sets of files. In this post, we introduce the Sort for testing and benchmarking Hadoop. The Sort program is also…