Re: Migrating to larger numbers

Augusto Cesar (bishop@sekure.org)
Mon, 31 May 1999 13:51:57 -0300 (EST)


On Mon, 31 May 1999, James McCollough wrote:

> > > > Okay, 2.3 is out; it's time to get some fundamental data types
> > > > expanded:
> > > >
> > > > REQUIRED:
> > > >
> > > > uid_t, gid_t: 32 bits minimum, 32 bits probably OK.
> > >
> > > Some ISPs and mail servers may have more than 65536 users on one system.
> > > I would propose to make uid_t and gid_t 64 bits.
> > >
> >
> > I vote for 32 bits, *some* ISPs have more than 65536 users, but they can
> > find others solutions, like using SQL databases for users accounts, if we
> > use a gid_t of 64 bits its more 32 bits for every gid_t variable, this
> > will increase up the size of kernel and decresing the speed with a feature
> > for only a couple of ISPs. IMHO.
> >
> 16-bit range = 0 to 2^16 = 0 to 65,535
> 32-bit range = 0 to 2^32 = 0 to 4,294,967,296
>
> unless you have more than 4.2 billion users, 32-bit uid_t and gid_t types
> should be adequate.
>

sorry, I confused with 16-bit, so reinforcing my opinion, 32 bits its the
best option, 64 bits never, will much increase the size of kernel.

16bit = 0 to 2^32 = 0 to 65,535
32bit = 0 to 2^32 = 0 to 4,294,967,296
64bit = 0 to 2^64 = 0 to 18,446,744,073,709,551,616

so what machine will have 18,446,744,073,709,551,616 of users? :-)

--
Augusto Cesar
Sekure SDI
http://www.sekure.org

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