Question for lower performance by using @threads in for loop

[brenhinkeller]

Threads can have have pretty high overhead – see for example

Julia Threads.@threads slower than single thread performance

Julia Threads.@threads slower than single thread performance

I am trying to solve numerically the heat equation in 1d: [enter image description here] I am using finite differences and I have some trouble using the @threads instruction in Julia. In particular below there are two version of the same code: the first one is single thread while the other uses @threads (they are identical apart from the @thread instruction) function heatSecLoop(;T::Float64) println("start") L = 1 ν = 0.5 Δt = 1e-6 Δx = 1e-3 Nt = ceil(Int, T/Δt ) …