Improving Build Times

Introduction

There are a number of things you can do in order to improve build times. These include:

• Using parallel invocations of make
• Suppressing compiler output on the console
• Using a compiler cache

Using parallel invocations of make

While make is set to run a single job serially by default, it able to run multiple jobs in parallel. You tell make to run parallel jobs (in the following example 4 jobs) by adding the following make option to your .mozconfig file:

mk_add_options MOZ_MAKE_FLAGS=-j4

Using the value 4 is a safe default on most dual core systems. Even on a single core machine, a value of j2 is a reasonable choice so that make isn't constantly blocked on I/O bound operations. You can experiment with different numbers of jobs for your particular hardware configuration.