V8 is fairly close to reaching a state where we can enable pointer compression. It will be a build time flag for the embedder to enable. Implications are:

• Significant memory savings. Some experiments show 30% smaller V8 heap size, in Chrome.
• Slightly worse performance, at least for now. We are confident that it could actually perform better.
• Upper limit of 4GB memory, at least for now.
• Different ABI, so Node modules for non-pointer-compressed builds are incompatible with pointer-compressed builds.

Discuss!