Dear list! Author: Salvatore Dipietro <dipi...@amazon.com> Number of patches: 1
This is an automated relay of the Github pull request: Adding 'sb' instruction for spin_delay for ARM v8.5 onward Patch title(s): Adding 'sb' instruction to spin_delay() for ARM v8.5 onward Link: https://github.com/haproxy/haproxy/pull/2974 Edit locally: wget https://github.com/haproxy/haproxy/pull/2974.patch && vi 2974.patch Apply locally: curl https://github.com/haproxy/haproxy/pull/2974.patch | git am - Description: We would like to propose this optimization for ARM architecture that, at runtime, it switches to SB instruction if supported by the system. SB (Speculation Barrier) is a modern barrier which is available from armv8.5a. It achieves the same result as issuing ISB, but instead of flushing the CPU it does so by serializing older instructions to be non-speculative before it completes. This is less disruptive than an "isb" to high performance CPUs. We already saw positive improvements on MySQL server (https://github.com/mysql/mysql- server/pull/611) and Folly (https://github.com/facebook/folly/pull/2390) implementations. Instructions: This github pull request will be closed automatically; patch should be reviewed on the haproxy mailing list (haproxy@formilux.org). Everyone is invited to comment, even the patch's author. Please keep the author and list CCed in replies. Please note that in absence of any response this pull request will be lost.
