Observe this usr@usr:~/julia_projects/uc/Uc$ julia --project=. --threads=1,0 _ _ _ _(_)_ | Documentation: https://docs.julialang.org (_) | (_) (_) | _ _ _| |_ __ _ | Type "?" for help, "]?" for Pkg help. | | | | | | |/ _` | | | | |_| | | | (_| | …

At the moment it is illegal to call GRBfreeenv on an environment because GRBfreeenv is called as part of the finaliser. One option is: julia> import Gurobi julia> env = Gurobi.Env(); Set parameter WLSAccessID Set parameter WLSSecret Set parameter LicenseID to value 722777 WLS license 722777 - reg…

I think for practical use cases, the Envs are allocated once. (For me, solving Gurobi models in parallel, I’ll have to allocate a vector of independent Envs.) So the Envs may not be needed to be freed manually by the user. But the models built on top of the Envs may required to be cleaned. Otherwi…

You need to ensure that there are no more references to the models in model_vec, nor any of their component parts like variables or constraints. Then, run the GC. An example would be: using JuMP, Gurobi const NUM_SCENARIOS = 3 const GUROBI_CONFIG = Dict{String,Any}("OutputFlag" => 0, "Threads" => …

Thanks. I’ll do some tests later on to see if that holds in my experiments. But before that, it appears that creating envs in parallel is significantly faster than an ordinary sequential loop. julia> import Gurobi julia> const C = Dict{String, Any}("OutputFlag"=>0,"Threads"=>1) julia> Env() = Gu…

It appears I still have memory leakage (I suspect that the memory allocated by Gurobi internally are leaked). Take a look at my experiment: usr@usr:~/julia_projects/uc/Uc$ ./j _ _ _ _(_)_ | Documentation: https://docs.julialang.org (_) | (_) (_) | _ _ _| |…

See also your previous question [image] Sometimes cannot reclaim memory by manual GC.gc() General Usage FYI this isn’t Julia, this is just the allocator in libc (Julia will even call that function automatically for you depending on the condition)

I tried julia> ccall(:malloc_trim, Int32, (Int32,), 0) 1 , (I’ve set all names to nothing, and then did gc() and executed the malloc_trim above.). But the memory usage can not be decreased (e.g. observing htop). In my code I built a vector of JuMP Models (Gurobi’s direct_model). Some memory was a…

I did a small test with this toy-example, which shows that GC.gc() is working normally, if all objects are defined locally inside functions. I guess I just need to write a all-encompassing main() function, like those I learnt in the C-programming language classroom.:smiling_face_with_tear: ▶ code

How to manage memory when using JuMP+Gurobi?

Specific Domains Optimization (Mathematical)

odow April 21, 2026, 7:28am 7

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How to manage memory when using JuMP+Gurobi?

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