Groups 198 of 99+ julia-users › everywhere and memory allocation 3 posts by 2 authors Pieterjan Robbe 12 1 15 does the everywhere macro allocate extra memory to make local copies of a matrix for every processor? A sprandn 10000,10000,0.7 time A sprandn 10000,10000,0.7 gives 2.422259 seconds 23 allocations: 1.565 GB, 3.77 gc time everywhere A sprandn 10000,10000,0.7 time everywhere A sprandn 10000,10000,0.7 gives 16.495639 seconds 1.31 k allocations: 1.565 GB, 6.14 gc time . However, I know that there are local copies of the matrix on each processor: everywhere println A 1,1 -1.2751101862102039 From worker 5: 0.0 From worker 4: 0.0 From worker 2: 0.853669869355948 From worker 3: 0.0 Is there a way to use the everywhere macro without allocating extra memory? Suppose A was created using A speye 10000,10000,0.7 is there also a copy of the matrix A for all of the workers? Andre Bieler 12 1 15 I think you are looking for shared arrays? http: docs.julialang.org en latest manual parallel-computing id2 Pieterjan Robbe 12 1 15 No, not really. SharedArrays do only support bitstypes. I have an application where the function to be executed in parallel depends on some fixed data some constants, a dict, some arrays, etc. I would like to replace my parallel for loop by everywhere because of the reuse of my cholesky factorization , but I'm worried that this will explode my memory usage.