<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Jun 26, 2017 at 7:24 PM, Friedman, Eli <span dir="ltr"><<a href="mailto:efriedma@codeaurora.org" target="_blank">efriedma@codeaurora.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<div class="m_-8178743545387745684moz-cite-prefix">On 6/19/2017 7:29 PM, Vedant Kumar
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<div>We can reduce testing time by *not*
instrumented basic tools like count, not,
FileCheck etc. I filed: <a href="http://llvm.org/PR33501" target="_blank">llvm.org/PR33501</a>.</div>
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<div>3. The generated profile
information takes up a lot of space: llc
generates a 90MB profraw file.<br>
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<div>I don't have any ideas about how to
fix this. You can decrease the space overhead for
raw profiles by altering <span>LLVM_PROFILE_</span><span>MERGE_P</span><span>O<wbr>OL_SIZE
from 4 to a lower value.</span></div>
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Disk space is cheap, but the I/O takes a long time. I
guess it's specifically bad for LLVM's "make check", maybe
not so bad for other cases.<br>
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<div>You can speed up "make check" a bit by using
non-instrumented versions of count, not, FileCheck, etc.</div>
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I tried looking into this a bit more. It looks like the profile
data file generated by llc contains approximately 5MB of counters
(__llvm_prf_cnts), 10MB of "data" (__llvm_prf_data), and 70MB of
__llvm_prf_names. __llvm_prf_data and __llvm_prf_names contain
which can be read from the original binary, as far as I can tell.
The 80MB of data wouldn't be a big deal if it were just sitting on
disk... but we also erase the whole file and rewrite it from scratch
after we merge profile counters.<br>
<br></div></blockquote><div><br></div><div>Can you check if name compression is turned on in your build? </div><div><br></div><div>David</div><div><br></div><div><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div text="#000000" bgcolor="#FFFFFF">
Can we do better here?<span class=""><br>
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-Eli<br>
<pre class="m_-8178743545387745684moz-signature" cols="72">--
Employee of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project</pre>
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