[Bug 735020] Re: Ubuntu 11.04: Support AMD Bulldozer processor - glibc (memset)
Turning off all SSEx routines for an issue with one routine (memcpy) will hurt performance quite a bit. Why not just stay at glibc 2.12 (with the memset changes we submitted to trunk) which will result in better performance and also deal with the memcpy issue? Or is the window for that closed? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/735020 Title: Ubuntu 11.04: Support AMD Bulldozer processor - glibc (memset) -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 735020] Re: Ubuntu 11.04: Support AMD Bulldozer processor - glibc (memset)
We looked at machine with Ubuntu 11.04 on it. And it looks like __memset_sse2 is not really avalaible in a dump of the glibc at /lib/x86_64-linux-gnu/libc.so.6. Nor is __memcpy_ssse3 avalaible. In fact, none of the symbols with _sse* suffix are avalaible. Does Ubuntu use glibc or eglibc? If glibc is used, is it built with --enable- multiarch. Without the *_sse* routines, we expect glibc performance to be quite hindered on both AMD Barcelona (Greyhound core) and AMD Orochi (Bulldozer core) machines. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/735020 Title: Ubuntu 11.04: Support AMD Bulldozer processor - glibc (memset) -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 735020] [NEW] Ubuntu 11.04: Support AMD Bulldozer processor - glibc (memset)
Public bug reported: Feature description: Backport patch to pick SSE2 version of x86-64 memset on AMD Bulldozer to Ubuntu 11.04 glibc. Partner benefit: memset shows up significantly in the profile of major apps and benchmarks. Since several Linux compilers like gcc, open64 etc rely on distribution glibc for string routines, this would make a significant difference to software performance readiness of AMD's upcoming Bulldozer processors. We are observing a 14% to 54% improvement in cycle counts for the SSE2 version of x86-64 memset compared to the integer version, for blocks between 144B and 8K. glibc trunk dispatches to integer version of memset on Bulldozer currently in trunk. The patch below fixes that. This patch also fixes the following bug in x86-64 memset - Currently for misaligned blocks 144B, based on the misalignment, memset code jumps into the integer code path even if the startup code explicitly chooses SSE2 for a processor. Development status: Submitted to mailing list. Upstream submission link with upstream submission status: Submitted at http://sourceware.org/ml/libc-alpha/2011-03/msg6.html ** Affects: glibc (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/735020 Title: Ubuntu 11.04: Support AMD Bulldozer processor - glibc (memset) -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
