On 6 April 2011 17:57, Heikki Linnakangas
<heikki.linnakangas@enterprisedb.com> wrote:
> On 06.04.2011 17:46, Tom Lane wrote:
>>
>> "Kevin Grittner"<Kevin.Grittner@wicourts.gov> writes:
>>>
>>> Robert Haas<robertmhaas@gmail.com> wrote:
>>>>
>>>> ... The one I'm most
>>>> worried about is "SSI: three different HTABs contend for shared
>>>> memory in a free-for-all" - because there's no patch for that yet,
>>>> and I am wary of breaking something mucking around with it.
>>
>>> I haven't seen any objection to Heikki's suggestion for how to
>>> handle the shared memory free-for-all:
>>
>> I confess to not having been reading the discussions about SSI very
>> much, but ... do we actually care whether there's a free-for-all?
>> What's the downside to letting the remaining shmem get claimed by
>> whichever table uses it first?
>
> It's leads to odd behavior. You start the database, and your application
> runs fine. Then you restart the database, and now you get "out of shared
> memory" errors from transactions that used to work.
>
> It's not the end of the world, but I'd prefer stable, repeatable behavior,
> even though having the slack shared memory be grabbed by whoever needs it
> first might in theory lead to better utilization of resources.
It sounds a bit apocalyptic to me, if that really is happening.
--
Thom Brown
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