|Summary:||pmcstat seems to be broken in sampling mode (at least on amd hardware)|
|Component:||bin||Assignee:||freebsd-bugs mailing list <bugs>|
|Severity:||Affects Only Me||CC:||cem|
Description shamaz.mazum 2018-12-24 07:41:50 UTC
Hello. I use FreeBSD 12.0-RELEASE on two machines (one with Ryzen 5 1600X processor and the other with FX-6300). Recently (presumable after upgrading to 12.0-RELEASE) pmcstat stopped working in sample mode. I run it as: `pmcstat -P instructions -O test.out -n 65536 ./noisecpu` on FX-6300 or `pmcstat -P ex_ret_instr -O test.out -n 65536 ./noisecpu` on Ryzen and then I run `pmcstat -R test.out -g` In both cases it creates directories (e.g. ex_ret_instr) which are either empty or containing only kernel.gmon `noisecpu` is computation heavy program, calculating value noise on a large grid and works for ~8 seconds. Conversion statistics usually looks like following: #exec/elf 1 #samples/total 169 #samples/unclaimed 165 #callchain/dubious-frames 165 In counting mode (with -p argument) everything seems to be working. Can anybody confirm this?