In order to improve the speed of software development one needs to be able to create faster development cycles and provide a shorter feedback loop. One of the ways to improve the development cycles is to reduce the time it takes to compile the project - if it is in a language where compilation is necessary.

The Linux kernel has 20 million lines of C code and I've just compiled in in 36 minutes on an old 4-core machine. PostgreSQL has 1 million lines of code and most of the build farm machines report 8-12 minute build time.

How long does it take to compile your software?

For comparison here are two Open Source projects:

How long does it take to compile the Linux kernel?

The Linux kernel has about 20 million lines of C code according to both the Linux counter and the OpenHub for Linux.

The compilation time will largely depend on the the configuration you have, so this number is not representative but I've just compiled it on an old 4-core machine and this is what time reported: 

real    36m49.545s
user    130m15.245s
sys     9m35.052s

So it used the 4 cores very well and it took 36 minutes to compile the kernel.

How long does it take to compile PostgreSQL?

According to the OpenHub on PostgreSQL it has about 1 million lines of C code.

Most of the machines in the PostgreSQL build farm report around 12-14 minutes. That includes both compilation and testing! Some machines took longer and a few ran in 8 minutes. I assume the differences are primarily due to the number of cores used in parallel.

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