Memory leak

[vchuravy]

Hey,

I am encountering a memory leak using OpenCL.jl

Execute the following in the REPL

import OpenCL; const cl = OpenCL
function leaky()
          device, ctx, queue = cl.create_compute_context()
          # Allocate buffer
          a = cl.Buffer(Float64, ctx, :rw, 1024*1024)
          cl.flush(queue)
          cl.release!(queue)
          cl.release!(ctx)
end

for i in 1:100000
   leaky()
end

gc()

Monitoring my process with htop I can see that Julia is now using ~400mb permanently, running the loop a second time results in an increase in memory of ~300mb.
This 300mb step is consistent over consecutive repetitions.

This happens to me both with the OpenCL implementation by Intel (CPU) and by Nvidia (although here I don't have any number available).

I am running Julia version 0.3.0-prerelease+2000 Commit 48ac426* (1 day old master) and OpenCL.jl current master.

If I try to manually release the Buffer with cl.release! I get an error about double freeing the Buffer.

Discussion on the mailing list: https://groups.google.com/forum/?fromgroups=#!topic/julia-dev/SRz6OkQ5hMw

Best,
Valentin