slow execution of built executables on a Mac
rae at cs.brynmawr.edu
Fri Oct 26 21:15:10 UTC 2018
> On Oct 26, 2018, at 5:02 PM, Carter Schonwald <carter.schonwald at gmail.com> wrote:
> are you setting the intree gmp flag? and/or dont have gmp the library installed? maybe your ghc is using integer simple!
Intriguing possibility. I haven't done anything to install gmp. I'm now at home, away from this machine, but I'll try this next week. I have a hunch you're right.
Perhaps we should have a warning when this is the case?
> theory two: dont set -j greater than about 8 or perhaps 16? (some parts of ghc are slower on too paralle a setup?)
I'm at -j5, so this isn't the problem.
> you could also look at system monitor to see if your'e being IO bound or memory or CPU bound
I tried this earlier, and it looked like I wasn't CPU-bound. I suspected a slow SSD somehow (if that's even possible). But watching the build this morning showed me that stage 1 is snappy while later work isn't, so that made me doubt my earlier guess. And installing the 6GB of LaTeX wasn't unduly slow, either.
> (possible failure siutation: the repo is under dropbox or something and dropbox is eating your memory bandwidth trying to sync stuff?)
Thanks for the idea, but I know to keep GHC away from Dropbox. :)
I'll give 90% confidence on the gmp thing.
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