Tom Lane wrote:
> What it comes down to is I don't want the postmaster to be keeping its
> own state in shared memory --- that is, the array must be write-only
> memory as far as the postmaster is concerned. If we eliminate the
Ok. Well, I can appreciate things from that point of view.
> postmaster's private DLList of backends, then the postmaster becomes
> that much more vulnerable to corruption from a backend bug that leads to
> trashing shared memory. To take just one example: backend A goes nuts,
> zeroes the whole shmem segment, and then dumps core. How is the
> postmaster going to kill the other backends so that it can begin the
> recovery process? If there's no record of their PIDs left anywhere,
> it's got a problem. The postmaster *needs* its own copy of that DLList.
> You might object that backend bugs could clobber the array and thus
> interfere with cancel request processing, but that's not nearly as
> critical a function.
Actually, if I was going to argue anything, I'd say that if a backend goes
nuts and zeroes the whole shmem segment you've probably some bigger things
to worry about (Aside: Would postgres actually recover from such an
occurence? BTW, I'd be pretty impressed if it did, but not all that
But I'll happily concede the point, and prove it by knocking up a patch for
it over the weekend (unless anyone else particularly wants to).
Certain disclaimers and policies apply to all email sent from Memetrics.
For the full text of these disclaimers and policies see
---------------------------(end of broadcast)---------------------------
TIP 6: Have you searched our list archives?