Yes, /dev/shm is ok on my computer.

But there is yet one drawback of this patch. Currently the size of shared array is limited by the free space on the file system for temporary files. If it isn't enough you can easy set TMPDIR to other path. In 2.7 and with hardcoded /dev/shm it is limited by the size of physical memory (maybe plus swap). It is not easy to increase it, especially for unprivileged user.

The effect of hardcoding /dev/shm can be achieved by setting TMPDIR to /dev/shm. Using os.ftruncate() adds yet about 20% of speed up. This looks mainly as a documentation issue to me. The regression and the workaround should be documented.