Wkhtmltopdf / Wkhtmltoimage x CentOS x Xen = Segfault Mania

The Behance Network uses a number of nifty little binary files to create some of the useful services that our platform offers. Two of them in particular are wkhtmltoimage and wkhtmltopdf ( both 64-bit static binary files ). These two files convert HTML to either a PDF or a thumbnail image of a full webpage and dumps the output. These tools work flawlessly on both our sandbox environments ( Ubuntu 11.04 ) and our production image servers ( CentOS 5.5 ). When we try to execute these files on one of our new Imageservice cloud servers ( CentOS 5.4 ),  we receive the dreaded:

“Segmentation fault”

Let’s start off with basics, what exactly is a segfault?

According to Wikipedia ( http://en.wikipedia.org/wiki/Segmentation_fault ):

A segmentation fault (often shortened to segfault) or bus error is generally an attempt to access memory that the CPU cannot physically address. It occurs when the hardware notifies a Unix-like operating system about a memory access violation. The OS kernel then sends a signal to the process which caused the exception. By default, the process receiving the signal dumps core and terminates.

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