Re: var_mailbox_limit 32bit limit

[Qi Yong]

On 04/03/2008, Wietse Venema <wietse@xxxxxxxxxxxxx> wrote:
> Leandro Santi:
>
> > On 3/1/08, Qi Yong <qiiyoong@xxxxxxxxx> wrote:
>  > > On 29/02/2008, Leandro Santi <lesanti@xxxxxxxxx> wrote:
>  > >  > On 2/29/08, Qi Yong <qiiyoong@xxxxxxxxx> wrote:
>  > >  >  >  var_mailbox_limit is int type. This caps mailbox_size_limit to 2147483647
>  > >  >  >  at the maximum. I'd like to make var_mailbox_limit a long integer. What do
>  > >  >  >  you think of this idea? And objections? I have large mboxs here. Thanks.
>
>
> Using long won't help, especially not when int==long like it is
>  on 32-bit boxes.

It should work. long are 64bit on Linux x86_64 or FreeBSD amd64. And
most if not all newer servers support that 'long mode'.

>
>  To handle >2GB files, you either need a grown-up OS, or you need

(Seems people here think Linux is 'toy operating' and not 'grown-up'.
Actually if you have to blame, you'd blame GNU, not the kernel.)

I think that GNU/Linux was supporting large file in a different way
from *BSD as you think was because they were afraid making off_t 64bit
would break old wrong things. And there are also other considerations.
Then they introduced off64_t or loff_t.

But the above does not cover all the facts. On Linux/x86_64, off_t is
64 bit too. The library has things like _FILE_OFFSET_BITS,
__USE_FILE_OFFSET64 and typedef __off64_t off_t, check
/usr/include/unistd.h.

>  to recompile Postfix in the large file model.

Is Postfix has a large file model?

>
>  However, that may or may not be sufficient. You may also have to
>  to recompile libraries that Postfix depends on in the large file
>  model.

I think the pre-built libraries in an amd64 distro are already done so.

So my proposal is using long for var_mailbox_limit et al in order to
get rid of the 2G limit on amd64. And if that is acceptable, I'd like
to try.
-- 
Qi Yong
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