Dumb newbie question of the day: Why does it take so long to compile a simple program? My system might be a bit dated, but I've done a lot of C/C++ coding on a lot of MCUs over the years on this machine using quite a few compilers. I realize that in addition to my small test programs, a lot of libra…

The compilation time significantly increased in Arduino IDE 1.6.6 and newer when they switched to a new preprocessing system. They've done some work on improving it in recent versions but it's still an amazing difference when I do a test compilation on 1.6.5 or older. I think part of it is the proce…

Turn on "verbose" for compilation in the "preferences" panel, and you can look for any specific bottlenecks (although my experiences is that when it's slow for some reason, it just runs EVERY STEP particularly slowly.) My last "this is slower than expected" experience went away as mysteriously as i…

I think you're definitely right about the priority. I've noticed that if I try to multitask by switching to the window of different application while the Arduino IDE is compiling it doesn't really progress at all until I switch back to the IDE window.

westfw: Turn on "verbose" for compilation in the "preferences" panel, and you can look for any specific bottlenecks (although my experiences is that when it's slow for some reason, it just runs EVERY STEP particularly slowly.) My last "this is slower than expected" experience went away as mysteri…

this slow Care to attach some quantitative numbers to that? My rather ancient (but otherwise pretty zippy - ) Mac takes about 9 seconds to compile blink the first time. An old single-core Laptop running W10 takes between 10 and 20s. I'd say that anything under 30s is "not unexpected." Both Verb…

I believe the core is now cached after the first compilation as long as you have File > Preferences > Aggressively cache compiled core checked. The IDE prints a message to the console that states the location of the archive when it is done on the first compilation.

pert: I believe the core is now cached after the first compilation as long as you have File > Preferences > Aggressively cache compiled core checked. The IDE prints a message to the console that states the location of the archive when it is done on the first compilation. Thanks. That option is i…

I remember one user reporting they had tracked down the cause of a slow compilation to some of the files being located on a network drive. Maybe it was their temporary build folder, I can't remember the exact details.

Its having contention with the anti-virus software.

I'm having the same problem since I started to use the "nano 33 BLE Sense". Compiling "Blink" was a matter of very few seconds for the "nano every", but takes at least 30 seconds for the BLE Sense. The first compile of "Blink" even took several minutes and put all 4 cores of my Win7 PC to maximum l…

Why is compilation so slow?

Development Tools IDE 1.x

gpetrowitsch June 10, 2020, 12:03pm 12

Disabling the Antivirus Tool definitely makes compile times a lot shorter.

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Why is compilation so slow?

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