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When visiting Harvard University I received an Emergency Alert directly on my phone, see below. Google Now Emergency Alert At first I thought that this was a kind of student hack, but others just received the same alerts. After inspection it contained additional information, shown below. Flood…
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Lawrence Livermore National Laboratory provides a suite of software packages for the solution of ordinary differential equations. This suite is called SUNDIALS. SUNDIALS consists of CVODE: solves initial value problems for ordinary differential equation (ODE) systems; successor of GEAR, EPISODE,…
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HipHop Virtual Machine says that HHVM can run WordPress. A more technical description of the HHVM can be found in Speeding up PHP-based development with HipHop VM. One of the main targets was to be as fast as the previous PHP to C++ translater. This goal has been achieved, see below…
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Gunnar Heinsohn (German Wikipedia, English Wikipedia) wrote a book with title Söhne und Weltmacht -- Terror im Aufstieg und Fall der Nationen in German. This book is about: youth bulge and its implication to criminal or war activity genocide property and possession This book can explain why…
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My recent project had some issues with hashing some 10 million numbers. To analyze the matter I wrote a small test program, see numberhash.c. I wanted to know which influence the following factors play: hashing just numbers (no alphabetic characters) ASCII vs. EBCIDC choice of hash function load…
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Here is a simple test program to call SHA1 hashing routine from OpenSSL. #include <stdio.h> #include <string.h> #include <openssl/sha.h> int main (int argc, char *argv[]) { unsigned long i, n; unsigned char md[1024]; if (argc <= 1) return 0; n…
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Peter Kankowski wrote a very interesting article on hashing functions. It compares a number of current hash functions and conducts some performance benchmarks. iSCSI CRC Meiyan Murmur2 XXHfast32 SBox (dead link: https://home.comcast.net/~bretm/hash/10.html) Larson XXHstrong32 Sedgewick Novak…
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Here is an article GNU C: Extensions to the C Language Family about extensions in GNU C vs. ANSI C. Nested functions, i.e., a function defined within another function Double-word integers, i.e., 64 bit signed and unsigned long long int and unsigned long long int Arrays of variable length, f(int z)…
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Recently I learned the hard way that IBM Enterprise COBOL compiler for z/OS (mainframe) cannot generate 8-byte long POINTER variables, but only 4-byte pointers. This means, you cannot use more than 2GB in COBOL on a mainframe. I.e., you cannot make use of AMODE=64 with COBOL on the mainframe. You…
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Generators (and therefore coroutines) are now part of PHP (Wikipedia) 5.5, as of 20-Jun-2013. Here is an example: function xrange($start,$end) { for ($i = $start; $i<=$end; ++$i) yield($i); } The Icon programming language (Wikipeda) was one of the first computer languages where…
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I read a short note in Heise, that in 2011 WordPress was one of the most popular CMS. The report compared Alfresco WCM CMSMadeSimple Concrete5 DotNetNuke Drupal e107 eZ Publish Joomla! Liferay MODx Movable Type OpenCms Plone SilverStripe Textpattern Tiki Wiki CMS…
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I ran below commands under different load for my Gigabyte GTX 560 graphic card. export LD_LIBRARY_PATH=$CUDA_PATH/lib64 time /usr/local/cuda/samples/sdk/0_Simple/matrixMul/matrixMul time /usr/local/cuda/samples/sdk/0_Simple/matrixMulCUBLAS/matrixMulCUBLAS I was interested in the value…
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I copy Brian Koberlein's explanations on the history of Kepler's law. Kepler’s first two rules, that the orbit of a planet is an ellipse, and that a line drawn from the Sun to a planet sweeps out area at a constant rate were proposed in 1609. While these rules allowed for a more accurate…
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There is a an INCITE program (HPC Call for Proposals), where one can apply for CPU/GPU intensive jobs, the link is INCITE. From the FAQ: The INCITE program is open to US- and non-US-based researchers and research organizations needing large allocations of computer time, supporting resources, and…
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Bisher habe ich mit der Firma Unitymedia ausschließlich positive Erfahrungen gemacht. Sie sind es wert, kurz festgehalten zu werden. Am 20. August 2009 habe ich bei Unitymedia Internet (20MBit/s) und Telefon bestellt. Am nächsten Tag stand ein Herr Niclas Roth von Computer-Füchse vor der Tür…
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For internet connection I use a cable modem EPC3208 from Cisco, which was supplied by the cable provider, Unitymedia in my case. It shows the following measurements regarding signal-to-noise ratio, modem is at 192.168.100.1: More information on this modem can be found here: Cisco EPC3208 (dead…
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Mainframe rehosting is about replacing the whole mainframe with one or multiple Linux boxes, or at times, move portions of the application landscape from the mainframe to Linux. Thereby you basically keep many of the hitherto used development- and runtime-environment, like COBOL, DB2, IMS, CICS,…
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Impressive numbers from WordPress.com: 827 terabytes of data, 400.000 new users, 7 million logins, 1 billion of pageviews. From March Wrap-Up, written by Matt Mullenweg: In March we brought you P2, an awesome theme perfect for short-form and group blogging, made with love by Automatticians. Next,…
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Loop unrolling is not only good for sequential programming, it has similar dramatic effects in highly parallel codes as well, see Unrolling parallel loops (local copy), also see #pragma unroll in the NVidia CUDA programming guide. Some bullet points of the presentation: More resources consumed per…
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