<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Tue, Nov 28, 2017 at 5:03 PM, Xidorn Quan <span dir="ltr"><<a href="mailto:me@upsuper.org" target="_blank">me@upsuper.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><u></u>





<div><span class="gmail-"><div>On Wed, Nov 29, 2017, at 10:55 AM, Ryan VanderMeulen wrote:<br></div>
<blockquote type="cite"><div dir="ltr"><div><p style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span class="gmail-m_481591251184157012size" style="font-size:small"><span class="gmail-m_481591251184157012highlight" style="background-color:transparent"><span class="gmail-m_481591251184157012colour" style="color:rgb(0,0,0)"><span class="gmail-m_481591251184157012font" style="font-family:Arial"><span class="gmail-m_481591251184157012highlight" style="background-color:transparent"><span class="gmail-m_481591251184157012colour" style="color:rgb(0,0,0)"><span class="gmail-m_481591251184157012font" style="font-family:Arial">* </span></span></span>The fsmonitor extension was re-disabled due to significant performance regressions for some common operations caused by watchman excessively polling the filesystem.</span></span></span></span><br></p></div>
<div><span class="gmail-m_481591251184157012size" style="font-size:small"><a href="https://ftp.mozilla.org/pub/mozilla/libraries/win32/MozillaBuildSetup-Latest.exe" target="_blank"></a><a href="https://ftp.mozilla.org/pub/mozilla/libraries/win32/MozillaBuildSetup-Latest.exe" target="_blank"></a></span><br></div>
<div><div><span class="gmail-m_481591251184157012size" style="font-size:small">If you're already using version 3.1 without issue, you probably don't need to pick up this release. You may want to consider disabling fsmonitor in the mean time, however. You can do that by making the change below to <mozilla-build>/python/<wbr>mercurial.ini:</span><br></div>
<div><span class="gmail-m_481591251184157012size" style="font-size:small"><a href="https://hg.mozilla.org/mozilla-build/rev/7a7753947603" target="_blank">https://hg.mozilla.org/<wbr>mozilla-build/rev/7a7753947603</a></span><br></div>
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</span><div>It isn't clear to me what performance issue it has.<br></div>
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<div>From the bug, I can see the issue gps raised on GitHub: <a href="https://github.com/facebook/watchman/issues/548" target="_blank">https://github.com/facebook/<wbr>watchman/issues/548</a><br></div>
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<div>So my question would be, does it affect building Firefox in subdirectory of working directory? If it does, then it sounds very serious and people should probably disable it. If it doesn't, maybe it isn't a too big deal, since I don't think most developers want to create tons of files frequently.<span class="gmail-HOEnZb"><font color="#888888"><br></font></span></div></div></blockquote><div><br></div><div>I noticed the problem just running `hg pull` and `hg update` operations. (pull because of changes to the .hg directory and update because of working directory changes.) I was seeing a ~10x slowdown for large operations.</div><div><br></div><div>Fortunately, the issue is now fixed in upstream watchman. So watchman should make a return in the next MozillaBuild. If you can't wait, the link to download the latest Watchman for Windows build can be found at <a href="https://facebook.github.io/watchman/docs/install.html#download-for-windows-beta">https://facebook.github.io/watchman/docs/install.html#download-for-windows-beta</a>. Extract that into your MozillaBuild install and revert <a href="https://hg.mozilla.org/mozilla-build/rev/7a7753947603">https://hg.mozilla.org/mozilla-build/rev/7a7753947603</a> to enable Watchman.<br></div></div></div></div>