The Intel topdown performance analysis method separates out frontend stalls (level 1) into latency (level 2) and bandwidth (level 2). A frontend latency stall is when 0 uops are issued at all because the frontend is waiting. A frontend bandwidth … Continue reading →
Phoronix posted an article comparing compilers on threadripper. The comparison uses gcc7/gcc8/llvm5/llvm6/llvm7 and AMD AOCC. All benchmarks were compiled with -O3 -march=native.
Continue reading →Phoronix posted an article measuring Spectre V4 changes. These tests happen with kernel patches for the Spectre 3a (rogue system register read) and Spectre 4 (speculative store bypass) fixes are applied to the kernel. There is an AMD whitepaper describing … Continue reading →
Phoronix posted an article comparing performance for newest release of Dragonfly BSD. The comparison made is between the old release (5.2) and the new release under development (5.3). Overall, performance looks improved from new to older release. Unclear how this … Continue reading →
I have added a basic tool “topdown” that is a wrapper to collect topdown metrics.
Continue reading →Phoronix posted an article benchmarking the newest AMD AOCC compiler. The article compares performance with gcc 7, gcc 8 and llvm 6. This article goes through some of the benchmarks to understand what is measured. Overall, not sure the benchmarks … Continue reading →
Phoronix posted an article benchmarking the window subsystem for linux. The comparisons are between Ubuntu 18.04 running in WSL vs. Ubuntu 18.04 running directly on the processor and the older WSL using Ubuntu 16.04.
Continue reading →Phoronix posted an an article measuring Ryzen 2600 and Ryzen 2700. The comparisons were a 9-way CPU comparison of new processors (7 AMD and 2 Intel). In this posting, I’ll look more at the workloads being tested.
Continue reading →After my previous post on backend analysis, I got a chance to look further breaking out backend stall statistics.
Continue reading →Phoronix posted an article about Clear linux. The goal was to look for changes in the system after all packages were rebuilt with GCC 8.1.
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