<div dir="ltr">Note that I've fixed one bad compile time regression quite recently, and we're bisecting to another one. We benchmarked the multithreading stuff pretty carefully, so I doubt its that. Have you tried reverting locally and reproducing?</div>
<div class="gmail_extra"><br><br><div class="gmail_quote">On Fri, Aug 1, 2014 at 1:05 PM, Tobias Grosser <span dir="ltr"><<a href="mailto:tobias@grosser.es" target="_blank">tobias@grosser.es</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Hi,<br>
<br>
I was just browsing my LNT performance builder and it seems within the last month we managed to increase compile time from 37 to 47 seconds for the bullet benchmark:<br>
<br>
<a href="http://llvm.org/perf/db_default/v4/nts/graph?plot.0=34.274.3&highlight_run=29054" target="_blank">http://llvm.org/perf/db_<u></u>default/v4/nts/graph?plot.0=<u></u>34.274.3&highlight_run=29054</a><br>
<br>
A similar pattern can be seen for MallocBench/gs/gs where we go from 5.3<br>
to 7.4 seconds.<br>
<br>
<a href="http://llvm.org/perf/db_default/v4/nts/graph?plot.0=34.301.3&highlight_run=29054" target="_blank">http://llvm.org/perf/db_<u></u>default/v4/nts/graph?plot.0=<u></u>34.301.3&highlight_run=29054</a><br>
<br>
One contributing patch seems to be the following one (surprisingly):<br>
<br>
Author: Chandler Carruth <<a href="mailto:chandlerc@gmail.com" target="_blank">chandlerc@gmail.com</a>><br>
Date: Fri Jun 27 15:13:01 2014 +0000<br>
<br>
Re-apply r211287: Remove support for LLVM runtime multi-threading.<br>
<br>
I'll fix the problems in libclang and other projects in ways that<br>
don't require <mutex> until we sort out the cygwin situation.<br>
<br>
git-svn-id: <a href="https://llvm.org/svn/llvm-project/llvm/trunk@211900" target="_blank">https://llvm.org/svn/llvm-<u></u>project/llvm/trunk@211900</a><br>
<br>
I also looked at the earlier performance regressions, but could not find any obvious commits that could have caused these regressions.<br>
<br>
This is mostly a drive by observation, but maybe someone is motivated to investigate this further.<br>
<br>
Cheers,<br>
Tobias<br>
</blockquote></div><br></div>