Re: Listen / Notify rewrite

Tom Lane wrote:
> "Greg Sabino Mullane" <greg(at)turnstep(dot)com> writes:
>> Talk of efficiency also seems silly here - using
>> shared memory is already way more efficient than our current listen/notify
>> system.
>
> Except that the proposed implementation spills to disk. Particularly if
> it has to have support for large payloads, it could very well end up
> being a lot SLOWER than what we have now.
>

True, but do you really consider it to be a common case that the notify
system gets soo bogged down that it starts to crawl? The problem would
be the collective size of notify structures + payloads and whether that
would fit in memory or not. This leads me to believe that the only
safety in smaller payloads is *possibly* a smaller chance of bogging it
down, but that all depends on the usage pattern of smaller vs. larger
payloads which is system specific.

--
Andrew Chernow
eSilo, LLC
every bit counts
http://www.esilo.com/