Rails at Scale
Posts
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Interprocedural Sparse Conditional Type Propagation
We prototyped an interprocedural static analysis tool using sparse conditional constant propagation. -
YJIT 3.4: Even Faster and More Memory-Efficient
It’s 2025, and this year again, the YJIT team brings you a new version of YJIT that is even faster, more stable, and more memory-efficient.
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Ruby 3.3's YJIT: Faster While Using Less Memory
This year, the YJIT team has been working hard to improve and optimize YJIT. We’re proud to say that the version of YJIT to be included with Ruby 3.3 is leaps and bounds ahead of Ruby 3.2’s. It provides better performance across the board, while also warming up faster and using less memory. The 3.3 release is also more robust, including a number of bug fixes along with an improved test suite. In this blog post, we share some early numbers.
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YJIT Is the Most Memory-Efficient Ruby JIT
This year, the YJIT team and I have gotten a paper accepted at MPLR 2023 (Managed Programming Languages and Runtimes), which is now freely available through ACM open access. The paper, titled “Evaluating YJIT’s Performance in a Production Context: A Pragmatic Approach”, goes into details of the strategy taken to evaluate YJIT’s performance in a production context. One of our key findings, when comparing YJIT against other existing Ruby JITs such as JRuby and TruffleRuby, is that YJIT is the most memory-efficient Ruby JIT (by a long shot).