Comment 3 for bug 1663280
Revision history for this message
| Oleg Strikov (strikov-deactivatedaccount) wrote Re: Serious performance degradation of math functions in 16.04/16.10/17.04 due to known Glibc bug | #3 |
Bug description has been updated to include the following information:
@strikov: According to a quite reliable source [5] all AMD CPUs and latest Intel CPUs (Skylake and Knights Landing) don't suffer from AVX/SSE transition penalty. It means that the scope of this bug becomes smaller and includes only the following generations of Intel's CPUs: Sandy Bridge, Ivy Bridge, Haswell, and Broadwell. Scope still remains quite large though.
@strikov: Ubuntu 16.10/17.04 which use Glibc 2.24 may recieve the fix from upstream 2.24 branch (as Marcel pointed out, fix has been backported to 2.24 branch where Fedora took it successfully) if such synchronization will take place. Ubuntu 16.04 (the main target of this bug) uses Glibc 2.23 which hasn't been patched upstream and will suffer from performance degradation until we fix it manually.