Installing Jenkins stable on RHEL7 minimal

Install prerequisites:

yum install java-1.8.0-openjdk-headless dejavu-sans-fonts fontconfig

Install Jenkins stable repo:

cd /etc/yum.repos.d/
curl -O
rpm --import

Install Jenkins:

yum install jenkins

Set Jenkins service to start at startup:

systemctl enable jenkins.service

Start Jenkins service:

systemctl start jenkins.service

Verify that Jenkins is listening on port 8080:

ss -ln | grep 8080

Note that even though Jenkins may be listening on 8080, don't forget to open your firewall appropriately.


/usr/bin/ld: cannot find -lz


/usr/bin/ld: cannot find -lz


yum install zlib-static


/usr/bin/ld: cannot find -lpthread


yum install glibc-static


/usr/bin/ld: cannot find -lstdc++


yum install libstdc++-static

If you are using RHEL7, these are in the rhel-x86_64-server-optional-7 channel.


How Does Hyperthreading Affect an ALLPATHS-LG Run?

In running ALLPATHS-LG, a short read genome assembler, on a Dell PowerEdge R920 with four Xeon E7-4860v2 processors running at 2.60GHz, I did one run with hyperthreading on and one with hyperthreading off. This was mainly to see if the increased cache size on the physical CPU core with hyperthreading off had a positive effect on performance.

I'll take all the anticipation away: Nope. Hyperthreading wins.

No Hyperthreading Hyperthreading
available cpus 24 48
GB of total available memory 1511.6 1511.6
hours of total elapsed time 30.32 28.81
hours of total per-module elapsed 30.33 28.82
hours of total per-module user time 357.57 630.52
effective parallelization factor 11.79 21.88
GB memory usage peak 457.13 457.13

How to Install Canon ip4000R Wireless Printer Driver on OS X 10.9

We have a wireless Canon PIXMA ip4000R printer that has served us well. However, a new computer with OS X 10.9 Mavericks did not recognize it, and Canon did not have a driver for it.

I ended up moving the following components from an existing computer on which the printer was already working:


I fixed the permissions:

sudo chown -R root:admin /Library/CFMSupport/
sudo chown -R root:wheel /System/Library/Extensions/BJUSBLoad.kext
sudo chown -R root:admin /Library/Printers/PPDs/

And finally, a link is needed for cups to work:

sudo ln -s /Library/Printers/Canon/BJPrinter/Plugins/BJNP/canonijnetwork.bundle/Contents/MacOS/canonijnetwork /usr/libexec/cups/backend/canonijnetwork

Before I was able to add the printer, I had to connect it via USB to the printer and add the USB version of the printer.

I was then able to add the Canon ijnetwork printer using the normal method of adding a printer in System Preferences. And delete the USB version.

Edit: now tested with OS X 10.10 Yosemite as well.


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