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<p class="MsoNormal">Hi Julian,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Have a look at this MR: <a href="https://gitlab.haskell.org/ghc/ghc/merge_requests/317">
https://gitlab.haskell.org/ghc/ghc/merge_requests/317</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">As soon as it lands, you’ll be able to run Hadrian builds with a local cache as follows:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">hadrian/build --shared=path/to/cache<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In this mode, build rules are cached, and if you happen to rerun a build rule with unchanged dependencies the resulting files will be copied from the cache instead of executing actual build commands.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This should significantly speed up switching between branches.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Note however that this does not give you a way to run distributed builds: at the moment it is not possible to offload any build rules to other machines.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-GB">Cheers,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-GB">Andrey<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">----------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Message: 1<o:p></o:p></p>
<p class="MsoNormal">Date: Sun, 17 Feb 2019 13:36:40 +1100<o:p></o:p></p>
<p class="MsoNormal">From: Julian Leviston <julian@leviston.net><o:p></o:p></p>
<p class="MsoNormal">To: GHC developers <ghc-devs@haskell.org><o:p></o:p></p>
<p class="MsoNormal">Subject: Distributed local dev builds<o:p></o:p></p>
<p class="MsoNormal">Message-ID: <86D5D29A-8839-4D0F-907F-029B626B5E3A@leviston.net><o:p></o:p></p>
<p class="MsoNormal">Content-Type: text/plain; charset=utf-8<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hi all,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have several fairly high-spec machines on my network where I usually build GHC, and I was wondering if it was easy/trivial/possible to set up a distributed build where it farmed out some of the compute work to the other machines? I seem
to need to build from scratch somewhat often when I switch branches I’m working on.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is this going to be the aim of distributed shake, which hadrian is based on?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks!<o:p></o:p></p>
<p class="MsoNormal">Julian<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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