Re: [Evolution] POP3 mbox performance and auto-expunging?

[Patrick O'Callaghan <poc usb ve>]

On Fri, 2008-08-22 at 09:03 +0200, Milan Crha wrote:
> On Thu, 2008-08-21 at 22:16 -0430, Patrick O'Callaghan wrote:
> > A 32-bit system might give a different result but I don't have one to
> > test. In any case, if there is a difference I would assume it to be
> > caused by an address-space limitation (or lack of available swap) rather
> > than a problem with the filesystem. AFAIK ext3 on 32 and 64-bit versions
> > of Linux is the same. Note that procmail and formail process their input
> > sequentially, so would not be subject to this kind of problem.
>
>       Hi,
> as far as I know, Evolution uses summaries to handle with mbox files
> (and with other types too), just to have quicker access to the mails.
> With mbox, there are stored offsets in the file to the beginning of the
> message. The problem on 32bit system is that the offset is signed int of
> 32bit size by default, (on 64bit it's 64bit signed int), so it breaks
> itself when trying to access mail on the offset greater than 2^31.

Thank you. This is a credible and sufficient explanation.

> It's possible to turn on large file support in compile time, but the
> problem is then with existing users, some migration should be done,
> because some information is stored only in the summary, not in the mbox
> file itself.

So the stored summary implicitly assumes the off_t size? I have to say
that I had no problems moving from a 32-bit to a 64-bit system and
preserving all my local mail, so I'm not sure there's really an issue
here (going the other way could be a different story of course).

poc