Hi all, We have enabled Thin LTO and LTO for a specific target architecture. What can be the possible scopes of improvement depending on the target after we enable the basic LTO and thin LTO.? Thanks, Siddharth -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20180502/8024d9d1/attachment.html>
I've only measured performance on x86. There are some old results for SPEC cpu2006 in the blog post here: http://blog.llvm.org/2016/06/thinlto-scalable-and-incremental-lto.html The benefit is benchmark dependent, e.g. small benchmarks often don't improve much as they don't require whole program optimizations. We've improved the ThinLTO optimizations since then, but I don't have any current numbers for SPEC handy. Note that the performance is higher if you combine with PGO as the two techniques are complementary. I would say 5-10% improvement is pretty common (when measured on top of PGO), for codes that can benefit from whole program / cross-module optimizations. Teresa On Tue, May 1, 2018 at 12:12 PM, Siddharth Shankar Swain via llvm-dev < llvm-dev at lists.llvm.org> wrote:> Hi all, > We have enabled Thin LTO and LTO for a specific target architecture. What > can be the possible scopes of improvement depending on the target after we > enable the basic LTO and thin LTO.? > Thanks, > Siddharth > > > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev > >-- Teresa Johnson | Software Engineer | tejohnson at google.com | 408-460-2413 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20180502/274283fa/attachment.html>
Hi, Thanks for the info, If i only want to run performance test on benchmarks for LTO and Thin LTO enabled target, Can u suggest ways to do it ? I want to do it at my end. Thanks, Siddharth On Wed, May 2, 2018 at 7:03 PM, Teresa Johnson <tejohnson at google.com> wrote:> I've only measured performance on x86. There are some old results for SPEC > cpu2006 in the blog post here: > http://blog.llvm.org/2016/06/thinlto-scalable-and-incremental-lto.html > The benefit is benchmark dependent, e.g. small benchmarks often don't > improve much as they don't require whole program optimizations. > > We've improved the ThinLTO optimizations since then, but I don't have any > current numbers for SPEC handy. > > Note that the performance is higher if you combine with PGO as the two > techniques are complementary. I would say 5-10% improvement is pretty > common (when measured on top of PGO), for codes that can benefit from whole > program / cross-module optimizations. > > Teresa > > On Tue, May 1, 2018 at 12:12 PM, Siddharth Shankar Swain via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > >> Hi all, >> We have enabled Thin LTO and LTO for a specific target architecture. What >> can be the possible scopes of improvement depending on the target after we >> enable the basic LTO and thin LTO.? >> Thanks, >> Siddharth >> >> >> _______________________________________________ >> LLVM Developers mailing list >> llvm-dev at lists.llvm.org >> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >> >> > > > -- > Teresa Johnson | Software Engineer | tejohnson at google.com | > 408-460-2413 >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20180511/5f04b7b9/attachment-0001.html>