Re: 2GB limit for temp_file_limit on 32bit platform

On 20/07/12 09:08, Joshua D. Drake wrote:
>
> On 07/19/2012 01:48 PM, Christopher Browne wrote:
>>
>> On Thu, Jul 19, 2012 at 4:29 PM, Joshua D. Drake
>> <jd(at)commandprompt(dot)com> wrote:
>>>
>>> On 07/19/2012 01:04 PM, Pavel Stehule wrote:
>>>>
>>>> I did a backport of temp_file_limit feature to 9.1, but when we tested
>>>> this patch, we found very restristrictive limit to 2GB.
>>>>
>>>> 2GB is nonsense, because this is session limit of temp files, and
>>>> these files should be longer than 2GB.
>>>
>>>
>>> I haven't read the patch but... don't all 32bit platforms have a 2GB
>>> limit
>>> (by default)?
>>
>> I don't think so.
>>
>> LFS got done in the mid-90s, which is long enough ago for people to
>> start forgetting about it. Are there any supported platforms that
>> didn't adopt LFS?
>>
>> http://en.wikipedia.org/wiki/Large_file_support
>
> Note: "by default" :). I know they could support LFS but as I recall
> you had to compile specifically for it (at least on linux and old
> versions of pg).
>
> So I was curious if it was that specific limitation or a limitation
> within the Pg code itself.
>
>

It is to do with the datatype of the GUC used for the setting - I
haven't got the patch in from of me to look at, but recall that going
larger meant using a float type which meant you couldn't get nice units
displayed (MB, GB etc).

I'll take a proper look later.

Cheers

Mark