Addendum to the previous comment: glibc version is 2.31-0ubuntu9. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1727136
Title: [GLIBC] Fix glibc AVX frequency problems Status in Linux: Triaged Status in linux package in Ubuntu: Triaged Bug description: Various glibc versions use AVX512 or AVX incorrectly in memcpy/memset or use AVX unintentionally due to branch mispredictions. On SKX using AVX can lower the frequency by several bins. There was a decision to not use AVX in memcpy/memset to avoid these problems for legacy code. glibc mainline has been fixed. The actual state per version depends on the version, and what backports it has applied. See the attachment for the fix status for several glibc versions. Need to figure out for each supported glibc release if they are affected, and submit backports of the fixes. How to test: Non AVX test code like compiles should not report any LVL1,2 AVX licenses with perf stat -e cpu/event=0x28,umask=0x18,name=core_power_lvl1_turbo_license/,cpu/event=0x28,umask=0x20,name=core_power_lvl2_turbo_license/,cpu/event=0x28,umask=0x40,name=core_power_throttle/,cycles -a -I 1000 sleep 10 17.10 also hit this issue, when testing, need run some others application. For example, building kernel. 16.04 hit the issue. Target Release: 16.04 To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1727136/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
