Found the answer. The problem was that SHMMAX was set to zero... or, rather, it was set to 137438953472, which was too large and resulted in zero. Thus, all shmgets would fail.

Setting this to a more sensible value solved the problem

In reply to Re: IPC-SysV problems when upgrading perl. by dancrumb
in thread IPC-SysV problems when upgrading perl. by dancrumb

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