Re: Dynamic Shared Memory stuff

On Thu, Dec 5, 2013 at 4:06 PM, Heikki Linnakangas
<hlinnakangas(at)vmware(dot)com> wrote:
>> That's a very interesting idea. I've been thinking that we needed to
>> preserve the property that new workers could attach to the shared
>> memory segment at any time, but that might not be necessary in all
>> case. We could introduce a new dsm operation that means "i promise no
>> one else needs to attach to this segment". Further attachments would
>> be disallowed by dsm.c regardless of the implementation in use, and
>> dsm_impl.c would also be given a chance to perform
>> implementation-specific operations, like shm_unlink and
>> shmctl(IPC_RMID). This new operation, when used, would help to reduce
>> the chance of leaks and perhaps catch other programming errors as
>> well.
>>
>> What should we call it? dsm_finalize() is the first thing that comes
>> to mind, but I'm not sure I like that.
>
> dsm_unlink() would mirror the underlying POSIX shm_unlink() call, and would
> be familiar to anyone who understands how unlink() on a file works on Unix.

OK, let me work on that once this CommitFest is done.

--
Robert Haas
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