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A comment on Threadripper 3990X: The Quest To Compile 1B Lines Of C++ On 64 Cores. Parent comment

Re:Threadripper 3990X: The Quest To Compile 1B Lines Of C++ ... by MayeulC on Wednesday February 03, 2021 @04:49PM (#26019619)
Well, you can always move your code to a ramdisk, I suspect any C(++) isn't more than a few GB anyway ?
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Re:Threadripper 3990X: The Quest To Compile 1B Lines Of C++ ... by flukus on Wednesday February 03, 2021 @08:41PM (#26021577)
Most compilers won't fsync will they? The output is likely not being written straight to disk.

It's caches all the way down.

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Re:Threadripper 3990X: The Quest To Compile 1B Lines Of C++ ... by rbanffy on Thursday February 04, 2021 @04:39AM (#26024046)
And to max out disk bandwidth before you max out your CPU cores you need a really terrible disk.

I don't think many 8-way Xeon Platinum boxes have eMMC storage.

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Re:Threadripper 3990X: The Quest To Compile 1B Lines Of C++ ... by MayeulC on Friday February 05, 2021 @02:11PM (#26040032)
Well, using ramdisks will let you compare and make sure the disk isn't the bottleneck, at least.
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Re:Threadripper 3990X: The Quest To Compile 1B Lines Of C++ ... by corty on Thursday February 04, 2021 @04:19AM (#26023961)
But all compilers will close(). Compare compile times on tmpfs and you will see an improvement.
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Re:Threadripper 3990X: The Quest To Compile 1B Lines Of C++ ... by nwmcsween on Friday February 05, 2021 @01:42AM (#26033755)
You don't even need to do this just cat all the files to /dev/null to prime the cache
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Re:Threadripper 3990X: The Quest To Compile 1B Lines Of C++ ... by biglost on Wednesday February 03, 2021 @08:37PM (#26021555)
With gentoo i use tmpfs and it works really well
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Re:Threadripper 3990X: The Quest To Compile 1B Lines Of C++ ... by bombcar on Thursday February 04, 2021 @04:39AM (#26024045)
Do you have details on how to enable this?
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Re:Threadripper 3990X: The Quest To Compile 1B Lines Of C++ ... by account42 on Thursday February 04, 2021 @10:40AM (#26026254)
Just mount a ramdisk over your portage TMPDIR (default /var/tmp/portage). You will need a decent amount of ram though for larger packages like LLVM. Disabling debug symbols will reduce the required space a bit.
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