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/dev/shm is now job-private like /tmp and /var/tmp in version 8.9. It was already restricted by cgroups but now in 8.9 jobs can't see other job's /dev/shm and it gets cleaned when a job exits. (tested krowe May 28, 2020)
Versions
It is unlikely there will be a version 8.8.10 but instead 9.0
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