multithreading - Julia and Lapack: pstrf multithreaded but trtrs not -

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my program written in julia not yield expected computational performance. program first computes cholesky decomposition of large matrix a using cholfact!, a = l'l. solves lx = b different b using backslash operator.

this results in straight calls lapack. function cholfact! implemented pstrf! , backslash operator uses trtrs!. these correct lapack functions use. while function pstrf! executed in parallel, function trtrs! not. profiler tells me of runtime spent on trtrs!. lines of code in program are

f = cholfact!(a, :l, pivot = true)     # precomputation, executed once

and

x = f[:l]\b[f.piv]    # inside loop, b computed x every step

why there difference between 2 lapack functions? how can parallel execution of pstrf!?


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