Distributions are a link in the Linux chain which users tend to place a lot of trust in. The reasonable assumptions are that a Linux distribution creator will keep the packages within the distribution up to date and secure, that the packages have been carefully selected and tested, and in the case of commercial Linux distributions, that bugs will be tracked and handled. But what happens when these assumptions aren't fulfilled?

Perl developers who use Red Hat Enterprise Linux recently got a shock when they benchmarked the Perl version supplied with Red Hat. Vipul Ved Prakash was involved in scaling up at a new startup and had just deployed a new 150-core system for their processing needs. But the expected performance boost did not appear. Vipul found that a Perl command named "bless" was running slowly, very slowly. The "bless" command is a pretty fundamental command and the overall impact on reading files made the Red Hat Perl one hundred time slower. This was not a new bug, but one that had been reported to Red Hat in 2007. The solution was simple; get the Perl source and build his own version of Perl. After installing it, Vipul reported performance improvements speed ups of well over one hundred times on their systems.

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