Default setting in imas2json takes forever to save

[eldond]

https://github.com/ProjectTorreyPines/IMASDD.jl/blob/7784a05b23b99b3d859c1fbc335dd0562049ffe8/src/io.jl#L347

The default of freeze=true with strict=false causes all the expressions to evaluate. A sparse IDS with freeze=false, strict=true can be saved rather quickly. A sparse IDS that tries to evaluate every expression while saving takes forever to save. I recommend changing the default behavior as the case for just dumping what's in the IDS to disk makes more sense. After all, that sparse dataset can be picked back up easily with json2imas and the expressions can then be evaluated.

[eldond]

BTW it's 5 seconds with strict=true/freeze=false and I killed the job after 5 minutes of it redlining my CPU fan the other way.

[orso82]

@eldond I suspect the problem is that freeze was traveling down the grid_ggd data structure. We were already marking anything under grid_ggd as not having expressions, but that was not taken into account by freeze!. I have pushed some fixed. Can you please try again?

[eldond]

With my settings from before that made it fast:

imas2json timing:  6.416736 seconds (15.98 M allocations: 1.384 GiB, 36.41% gc time)

With default timing (no custom freeze or strict keywords):
killed it after a few minutes of CPU GO BRRRRR

To reproduce:

1. Check out branch imas in SD4SOLPS
2. Edit test/runtests.jl to remove freeze and strict keywords in @time IMASDD.imas2json(dd, filename * ".json", strict=true, freeze=false)
3. Optional to save time: restrict test to the topic of interest with newARGS=["--preparation"]
4. Run the test, such as with include("test/runtests.jl")

IMASDD is v1.0.1 @ 10d751f
IMAS @ 97ecd4ee65a31f0195ee48c45b22879179ed3d05