Summary This PR implements JDK-8326205, introducing experimental support for grouping hot code within the CodeCache. Problem Modern CPUs use the branch target buffer (BTB), part of the branch predi...

A trip through HotSpot's C2 branch-to-cmov heuristic: it measures branch bias, not predictability, and in a tight loop that mismatch is worth up to 2.9x.

A deep dive into the known-bits abstraction that recently landed in HotSpot's C2 JIT compiler: the same tristate-bit abstraction LLVM and GCC use, and why it lets the JVM delete redundant masks and sh...

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A deep dive into an OpenJDK commit that replaced slow /proc file parsing with a single syscall, revealing obscure Linux kernel internals and a 20-year-old optimization opportunity.

A collection of modern/faster/saner alternatives to common unix commands. - ibraheemdev/modern-unix

How I investigated and worked around a kernel bug that caused async-profiler to freeze my machine whenever I tried to use a profiler.

Hi everyone! An ongoing reorganization at my current employer has prompted me to seek for a new role and would appreciate your support. I'm open to remote (anywhere) and hybrid roles in Switzerland (...

How a phantom single quote from bash's set -x caused random CI build failures through a race condition between stdout and stderr in Azure Pipelines.

A compiler deep-dive tracing Rust’s AtomicU64::fetch_max from macro expansion and rustc intrinsics through LLVM’s atomicrmw umax and AtomicExpandPass to the final x86-64 CAS loop

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A brief, pulls-no-punches, fast-paced introduction to the main design aspects of modern processor microarchitecture.

ALT: a cartoon of a devil with a speech bubble that says " lol "