<div dir="ltr"><div class="gmail_extra"><div><div class="gmail_signature" data-smartmail="gmail_signature">On Thu, Feb 1, 2018 at 10:06 AM, Rafael Avila de Espindola <span dir="ltr"><<a href="mailto:rafael.espindola@gmail.com" target="_blank">rafael.espindola@gmail.com</a>></span> wrote:<br></div></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">Rafael Avila de Espindola <<a href="mailto:rafael.espindola@gmail.com">rafael.espindola@gmail.com</a>> writes:<br>
<br>
</span>I tested the patch by linking chromium.<br>
<br>
With the last version of the patch I can measure a small improvement in<br>
L1-icache-load-misses. Somehow iTLB-load-misses seems to get worse:<br>
<br>
 Performance counter stats for './default-ld.lld @response.txt -o t --no-threads' (20 runs):<br>
<br>
           279,008      iTLB-load-misses                                              ( +-  0.36% )<br>
        17,916,925      L1-icache-load-misses                                         ( +-  0.19% )<br>
<br>
       1.165371143 seconds time elapsed                                          ( +-  0.12% )<br>
<br>
<br>
 Performance counter stats for './sorted-ld.lld @response.txt -o t --no-threads' (20 runs):<br>
<br>
           289,396      iTLB-load-misses                                              ( +-  0.77% )<br>
        16,922,395      L1-icache-load-misses                                         ( +-  0.18% )<br>
<br>
       1.166535009 seconds time elapsed                                          ( +-  0.12% )<br>
<br>
Do you have a suggestion of an open source program that might benefit<br>
more from this optimization?<br>
<br>
Cheers,<br>
Rafael<br></blockquote><div><br></div><div>I don't expect this patch to have a large impact on lld as its working set is rather small. Peter Collingbourne previously tested this patch on Chrome and got rather good results. He's already CCed, so I pinged him on IRC to see if he can chime in.</div></div><br></div><div class="gmail_extra">

<span style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">- Michael Spencer</span>

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