Re: Fix for large file support (nonsegment mode support)

Tom Lane wrote:
> [ redirecting to -hackers for wider comment ]
>
> Zdenek Kotala <Zdenek(dot)Kotala(at)Sun(dot)COM> writes:
>> Tom Lane wrote:
>> LET_OS_MANAGE_FILESIZE is good way. I think one problem of this option I
>> fixed. It is size of offset. I went thru the code and did not see any
>> other problem there. However, how you mentioned it need more testing. I
>> going to take server with large disk array and I will test it.
>
>> I would like to add --enable-largefile switch to configure file to
>> enable access to wide group of users. What you think about it?
>
> Yeah, I was going to suggest the same thing --- but not with that switch
> name. We already use enable/disable-largefile to control whether 64-bit
> file access is built at all (this mostly affects pg_dump at the moment).
>
> I think the clearest way might be to flip the sense of the variable.
> I never found "LET_OS_MANAGE_FILESIZE" to be a good name anyway. I'd
> suggest "USE_SEGMENTED_FILES", which defaults to "on", and you can
> turn it off via --disable-segmented-files if configure confirms your
> OS has largefile support (thus you could not specify both this and
> --disable-largefile).
>

There is latest version of nonsegment support patch. I changed
LET_OS_MANAGE_FILESIZE to USE_SEGMENTED_FILES and I added
-disable-segmented-files switch to configure. I kept tuplestore behavior
and it still split file in both mode.

I also little bit cleanup some other datatypes (e.g int->mode_t).
Autoconf and autoheader must be run after patch application.

I tested it with 9GB table and both mode works fine.

Please, let me know your comments.

Zdenek