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On Thu, Aug 25, 2011 at 9:16 AM, Dale <rdalek1967@×××××.com> wrote: |
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> Michael Mol wrote: |
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>> |
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>> Sometimes. My understanding is that it comes from packages which are |
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>> badly constructed, and can't reliably handle parallel builds. I'm told |
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>> that these cases are bugs and should be reported. Sometimes, if I |
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>> watch build output fly by, I'll even see something like |
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>> |
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>> make -j10 -j1 (some target name) |
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>> |
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>> where a maintainer decided to put an overriding -j1 after MAKEOPTS. |
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>> |
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>> |
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>> About two years ago, I found that, on my system (quad-core AMD Phenom |
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>> 9650), -j8 resulted in the fastest build time, as measured by building |
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>> ffmpeg.[1] Currently, I'm running -j10, and that's because I've been |
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>> using distcc to pass a couple compile tasks off to other systems. |
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>> (Though with the box I was deferring to scrapped for parts, I'll drop |
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>> this down to -j8 again) |
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>> |
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>> [1] Tested by building in tmpfs. You can find my data here: |
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>> |
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>> http://multimedia.cx/eggs/ffmpeg-and-multiple-build-threads/#comment-150325 |
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>> |
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>> |
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> |
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> This is interesting. I changed mine to j8 too. See how this works. CPUs |
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> are so fast nowadays, they can do a lot pretty fast. I'm trying to imagine |
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> 10 years from now. O_O |
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|
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I imagine there's a *lot* of money to be made researching AST |
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optimization and simplification transform searches as delegated to |
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GPUs. I don't imagine it'll speed up compiling much, but I do imagine |
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the resulting optimized programs will run far faster. Especially if |
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there's a trend toward declarative programming languages. (I wonder if |
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there's a Prolog implementation that dispatches work to OpenCL. I'm |
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surprised the Mozart/Oz folks haven't dug in that direction yet.) |
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|
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-- |
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:wq |
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