4 ms·
The "5-7%" improvement is in terms of build time, but no mention is made of any potential performance impact to users at runtime.
by nerdile 2y ago
The "5-7%" improvement is in terms of build time, but no mention is made of any potential performance impact to users at runtime.
- canucker2016 2y agoThe reference blog entry that the article refers to has further explanation - see https://ubuntu.com//blog/profile-guided-optimization-a-case-study https://ubuntu.com//blog/profile-guided-optimization-a-case-... Summary (for building OpenSSL, Emacs, GDB, and Python) - "QEMU will be profiled only when building OpenSSL, and a new QEMU will be built using profiling data from this build" The 5-7% improvement is seen when using QEMU on an x64 CPU to emulate a RISC-V CPU to build the 4 previously mentioned software projects. So if you're building software that uses C, you'll probably see 5-7% improvement in RISC-V build times on an AMD x64 CPU. I recall that Meta's BOLT optimizer can extract further reduction by optimizing software that has already been through PGO/FDO. ...assuming your workload matches the profiled workload. see https://github.com/llvm/llvm-project/blob/main/bolt/docs/OptimizingLinux.md https://github.com/llvm/llvm-project/blob/main/bolt/docs/Opt...