Re: Fix for large file support - Mailing list pgsql-patches

From Tom Lane
Subject Re: Fix for large file support
Date
Msg-id 14547.1175879048@sss.pgh.pa.us
Whole thread Raw
In response to Re: Fix for large file support  (Zdenek Kotala <Zdenek.Kotala@Sun.COM>)
Responses Re: Fix for large file support  (Zdenek Kotala <Zdenek.Kotala@Sun.COM>)
List pgsql-patches
Zdenek Kotala <Zdenek.Kotala@Sun.COM> writes:
> Andrew Dunstan wrote:
>> Or give better performance?

> Yes. List of chunks is stored as linked list and for some operation
> (e.g. expand) are all chunks opened and their size is checked. On big
> tables it takes some time. For example if you have 1TB big table and you
> want to add new block you must go and open all 1024 files.

Indeed, but that would be far more effectively addressed by fixing the
*other* code path that doesn't segment at all (the
LET_OS_MANAGE_FILESIZE option, which is most likely broken these days
for lack of testing).  I don't see the point of a halfway measure like
increasing RELSEG_SIZE.

            regards, tom lane

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