Linux ASI Performance Breakthrough: From 70% to 13% I/O Overhead Reduction

For years, Google engineers have been working on Address Space Isolation (ASI) for the Linux kernel to combat growing CPU speculative execution vulnerabilities. Early implementations resulted in a crippling 70% I/O throughput penalty. Now, that overhead is down to just 13%. Google engineer Brendan Jackman has revived the effort, presenting a solution to the page cache performance issues. While challenges remain, particularly concerning context switching and copy-on-write operations, the significant progress makes ASI a viable contender for a mainstream CPU vulnerability solution.