Posts By: jonny

Intel Xeon Phi Co-Processor Setup

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Introduction Just adding my notes here in case it helps anyone else who finds themselves in a similar situation to me.I have two machines each with an Intel Xeon Phi Co-Processor board. This (in my basic view of the world) is like an extra machine inside the host machine but contains 240 processors clocking in… Read more »

Bulk Delete Emails in Gmail

Gmail bulk delete messages

I had a bunch of emails sent from one of my own automated notification systems that I wanted to remove from Gmail. Doing a search in Gmail showed the first batch of 50 emails but the key to removing them all in one go is when ticking the ‘Select All’ checkbox (see below) a message… Read more »

Solar Power Installation

Solar Panels on Roof

Just thought I would record a few notes/thoughts on my recent solar installation in case I need to illustrate it to anyone I know. For the solar photovoltaic (PV) panels there was two choices: Sharp (Japanese) or SolarWorld (German) panels. According to David (our installer) there is little difference bar aesthetics, although the Sharp ones… Read more »

CyanogenMod on the Samsung Galaxy Tab 2

cyanogenmod clockwork recovery image

I wanted to breath a little new life into a Galaxy Tab 2 (model P3110) that was about 18 months old, so dusting it off I followed the instructions on the CyanogenMod wiki. Roughly the steps were as follows: I downloaded and installed the Heimdall tool to my desktop computer I downloaded the Clockwork Mod… Read more »

Building Likwid RPMs for CentOS

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Installing likwid is easy (using ./configure, make, make install) however I wanted to create an RPM package to allow for repeatable builds and installation across a number of nodes/machines. With the ‘Development Tools’ package installed I started with:

I downloaded the latest likwid release (3.1.3) and copied it to

Then moved to the… Read more »

MySQL dummy placeholder RPM package for MariaDB

On CentOS 7 MariaDB has (quite rightfully IMHO) replaced MySQL in the repositories however this has caused me a few problems. Since MySQL was so widely used there are other things that have MySQL as a requirement/dependency. Mainly my problem was some puppet modules that wanted the mysql-server package installed before they would proceed with… Read more »

Local Ubuntu Repository

I wanted to set up a local repository for DEB packages I create to be installed among a number of cluster nodes. After building the deb package I added it to my home folder as follows and created the Packages.gz file:

I can now add a new line to my apt sources.list file as… Read more »

Nginx Reverse Proxy

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Using CentOS 6 I installed Nginx with:

and amended the config file for the default website i.e.

With the following content:

So visiting the web address frontend.domain.co.uk:8080 as configured under the ‘server’ section will proxy the website from st.domain.co.uk:80 Advice on the web specified using $host or configuring the proxy_set_header:

However,… Read more »

Selectively Checking Disk Usage Excluding Files and Folders

disk usage

Normally to check the disk usage of directories on a linux system I would run:

However, occasionally I want to exclude particular directories that take a long time to check and/or that I am not interested in anyway. The example below run from the root of the filesystem skips checks for /home /local /var… Read more »