From: s.wanabe@... Date: 2018-11-09T00:17:42+00:00 Subject: [ruby-core:89761] [Ruby trunk Feature#15085] Decrease memory cache usage of MJIT Issue #15085 has been updated by wanabe (_ wanabe). File benchmark-with-perf-on-preview3.log added The issue is almost gone on v2_6_0_preview3. `invokesuper` on MJIT runs as about fast as on normal VM. Attached "benchmark-with-perf-on-preview3.log" is benchmark result. ---------------------------------------- Feature #15085: Decrease memory cache usage of MJIT https://bugs.ruby-lang.org/issues/15085#change-74815 * Author: wanabe (_ wanabe) * Status: Rejected * Priority: Normal * Assignee: * Target version: ---------------------------------------- MJIT makes ruby-methods faster by ordinary, but I have observed that some cases are exceptional. I guess the one is caused by `invokesuper` instruction. And I guess it is related to memory caching, especially iTLB. Attached "export-big-func.patch" makes MJIT binary code for `invokesuper` smaller. "super.rb" is a benchmark script with benchmark_driver. "benchmark.log" is a result of super.rb. "benchmark-with-perf.log" is another result with `PERF_STAT` environment variable. The results are merely in my environment and depend to a large part on machine specs. `invokesuper` can get faster with exported `vm_search_super_method()`, but I think it is not enough. Because `perf stat` shows that there are still many iTLB-load-misses. I believe MJIT can grow fast with good care for CPU memory cache, not only iTLB but also L1 / L2 and so on. ---Files-------------------------------- export-big-func.patch (934 Bytes) super.rb (897 Bytes) benchmark.log (624 Bytes) benchmark-with-perf.log (7.05 KB) export-vm_call_super_method.patch (2.66 KB) benchmark-with-perf-on-preview3.log (9.99 KB) -- https://bugs.ruby-lang.org/ Unsubscribe: