hangs during plan_rfft

[ssfrr]

I'm having trouble reproducing this reliably, but I've been seeing strange behavior when using plan_rfft. So far I've only seen it in Juno, so it may have something to do with threading, but I've also tried starting julia from the command line with multiple threads and haven't been able to reproduce it. I think I saw it within Juno with nthreads() == 1 but it's possible there was some lingering configuration because of the cycler, so take that with a grain of salt.

The code I've been running looks more or less like:

L = 443414 # length of one of the samples I was testing with
v = randn(nextfastfft(L));
plan_rfft(v; flags=FFTW.MEASURE | FFTW.DESTROY_INPUT)

For a while my CPU chugs along as expected, but then my CPU usage drops like it's done, but the function still doesn't return. It seems like something is waiting for a result that never comes or something.

Here's all the info on my Julia environment:

Atom:

Version: 1.43.0
Dev Mode: false
Official Release: true
{
"http_parser": "2.8.0",
"node": "10.11.0",
"v8": "6.9.427.31-electron.0",
"uv": "1.23.0",
"zlib": "1.2.11",
"ares": "1.14.0",
"modules": "69",
"nghttp2": "1.33.0",
"napi": "3",
"openssl": "1.1.0",
"electron": "4.2.7",
"chrome": "69.0.3497.128",
"icu": "62.2",
"unicode": "11.0",
"cldr": "33.1",
"tz": "2019a"
}

julia-client:

Version: 0.12.0
Config:
{
"firstBoot": false,
"juliaOptions": {
"bootMode": "Basic",
"noAutoParenthesis": true,
"numberOfThreads": "1"
},
"juliaPath": "/home/sfr/local/bin/julia",
"remoteOptions": {
"tmux": true
},
"uiOptions": {
"enableMenu": true,
"enableToolBar": true
}
}

ink:

Version: 0.12.0
Config:
{
"monotypeResults": true
}

uber-juno:

Version: 0.3.0
Config:
{
"disable": true
}

language-julia:

Version: 0.19.2
Config:
undefined

language-weave:

Version: 0.6.7
Config:
undefined

indent-detective:

Version: 0.4.0
Config:
undefined

latex-completions:

Version: 0.3.6
Config:
undefined

versioninfo():

Julia Version 1.3.1
Commit 2d5741174c (2019-12-30 21:36 UTC)
Platform Info:
OS: Linux (x86_64-pc-linux-gnu)
CPU: Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz
WORD_SIZE: 64
LIBM: libopenlibm
LLVM: libLLVM-6.0.1 (ORCJIT, skylake)
Environment:
JULIA_EDITOR = atom -a
JULIA_NUM_THREADS = 1
JULIA_PKG_DEVDIR = /home/sfr/Dropbox/juliadev

Status `~/research_journal/2020/02/18/fftw_benchmarks/Project.toml`

[717857b8] DSP v0.6.3
[7a1cc6ca] FFTW v1.2.0
[91a5bcdd] Plots v0.28.4
[295af30f] Revise v2.5.1
[44d3d7a6] Weave v0.9.1

[ssfrr]

It seems that there have been some other reports of this kind of thing within Juno, so I think maybe this isn’t an FFTW problem after all. I’ll close and re-open later if I can confirm it’s not Juno-related.