Re: Dynamic Shared Memory stuff

On Fri, Apr 4, 2014 at 10:01 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Wed, Jan 22, 2014 at 10:17 AM, Noah Misch <noah(at)leadboat(dot)com> wrote:
>> Yeah, abandoning the state file is looking attractive.
>
> Here's a draft patch getting rid of the state file. This should
> address concerns raised by Heikki and Fujii Masao and echoed by Tom
> that dynamic shared memory behaves differently than the main shared
> memory segment. The control segment ID is stored in the System V
> shared memory block, so we're guaranteed that when using either System
> V or POSIX shared memory we'll always latch onto the control segment
> that matches up with the main shared memory segment we latched on to.
> Cleanup for the file-mmap and Windows methods doesn't need to change,
> because the former always just means clearing out $PGDATA/pg_dynshmem,
> and the latter is done automatically by the operating system.
>
> Comments?

Apparently not. However, I'm fairly sure this is a step toward
addressing the complaints previously raised, even if there may be some
details people still want changed, so I've gone ahead and committed
it.

--
Robert Haas
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