Reduce default thread count

[solidiquis]

Setting default thread count to available_parallelism takes us way past the point of diminishing returns which is actually detrimental to performance.

3 seems to be the sweet spot I've found across various SSDs and HDDs.

For more information about how parallelism affects disk reads checkout this link.

┌─ code
└ 🧋 time et -l 1 -H -i -t 1 --no-config
code (125.46 GiB)
├─ ruby (32.87 KiB)
├─ advent_of_code (3.81 MiB)
├─ lua (21.02 KiB)
├─ homebrew-tap (33.93 KiB)
├─ rust (6.52 GiB)
├─ projects (118.94 GiB)
├─ test (25.55 KiB)
├─ .DS_Store (6.00 KiB)
└─ golf (2.30 KiB)

et -l 1 -H -i -t 1 --no-config  1.06s user 0.88s system 121% cpu 1.597 total
┌─ code
└ 🧋 time et -l 1 -H -i -t 2 --no-config
code (125.46 GiB)
├─ ruby (32.87 KiB)
├─ advent_of_code (3.81 MiB)
├─ lua (21.02 KiB)
├─ rust (6.52 GiB)
├─ homebrew-tap (33.93 KiB)
├─ projects (118.94 GiB)
├─ .DS_Store (6.00 KiB)
├─ test (25.55 KiB)
└─ golf (2.30 KiB)

et -l 1 -H -i -t 2 --no-config  1.03s user 1.02s system 209% cpu 0.979 total
┌─ code
└ 🧋 time et -l 1 -H -i -t 3 --no-config
code (125.46 GiB)
├─ ruby (32.87 KiB)
├─ advent_of_code (3.81 MiB)
├─ lua (21.02 KiB)
├─ homebrew-tap (33.93 KiB)
├─ projects (118.94 GiB)
├─ rust (6.52 GiB)
├─ test (25.55 KiB)
├─ .DS_Store (6.00 KiB)
└─ golf (2.30 KiB)

et -l 1 -H -i -t 3 --no-config  1.10s user 1.14s system 281% cpu 0.796 total
┌─ code
└ 🧋 time et -l 1 -H -i -t 4 --no-config
code (125.46 GiB)
├─ ruby (32.87 KiB)
├─ lua (21.02 KiB)
├─ advent_of_code (3.81 MiB)
├─ rust (6.52 GiB)
├─ homebrew-tap (33.93 KiB)
├─ projects (118.94 GiB)
├─ .DS_Store (6.00 KiB)
├─ golf (2.30 KiB)
└─ test (25.55 KiB)

et -l 1 -H -i -t 4 --no-config  1.19s user 1.61s system 339% cpu 0.828 total
┌─ code
└ 🧋 time et -l 1 -H -i -t 5 --no-config
code (125.46 GiB)
├─ ruby (32.87 KiB)
├─ advent_of_code (3.81 MiB)
├─ lua (21.02 KiB)
├─ homebrew-tap (33.93 KiB)
├─ rust (6.52 GiB)
├─ projects (118.94 GiB)
├─ test (25.55 KiB)
├─ .DS_Store (6.00 KiB)
└─ golf (2.30 KiB)

et -l 1 -H -i -t 5 --no-config  1.29s user 2.05s system 399% cpu 0.836 total
┌─ code
└ 🧋 time et -l 1 -H -i -t 6 --no-config
code (125.46 GiB)
├─ ruby (32.87 KiB)
├─ lua (21.02 KiB)
├─ rust (6.52 GiB)
├─ .DS_Store (6.00 KiB)
├─ homebrew-tap (33.93 KiB)
├─ advent_of_code (3.81 MiB)
├─ projects (118.94 GiB)
├─ test (25.55 KiB)
└─ golf (2.30 KiB)

et -l 1 -H -i -t 6 --no-config  1.35s user 2.56s system 463% cpu 0.844 total