Re: getting to beta

From: Thom Brown <thom(at)linux(dot)com>
To: Heikki Linnakangas <heikki(dot)linnakangas(at)enterprisedb(dot)com>
Cc: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Kevin Grittner <Kevin(dot)Grittner(at)wicourts(dot)gov>, Robert Haas <robertmhaas(at)gmail(dot)com>, Dan Ports <drkp(at)csail(dot)mit(dot)edu>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: getting to beta
Date: 2011-04-06 17:01:11
Message-ID: BANLkTikbcRgumwsRxB3U1DHeF+rCBdXyog@mail.gmail.com
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On 6 April 2011 17:57, Heikki Linnakangas
<heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:
> On 06.04.2011 17:46, Tom Lane wrote:
>>
>> "Kevin Grittner"<Kevin(dot)Grittner(at)wicourts(dot)gov>  writes:
>>>
>>> Robert Haas<robertmhaas(at)gmail(dot)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
Twitter: @darkixion
IRC (freenode): dark_ixion
Registered Linux user: #516935

EnterpriseDB UK: http://www.enterprisedb.com
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