Re: max_loop limit

devzero
2007-03-22T13:53:23Z

oh - i forgot sending this to the list, since this was copy&paste via webmailer.....

> -----Ursprüngliche Nachricht-----
> Von: devzero@web.de
> Gesendet: 22.03.07 14:42:45
> An: tomas@slax.org
> CC: breeves@redhat.com
> Betreff: Re: max_loop limit

> Hi Tomas,
>
> you`re completely right.
>
> I have had this problem of loopdev number limitation for years, but i think there is a better solution besides your patch.
>
> Some new module has been created for this and being announced on dm-devel mailinglist :
>
> dm-loop - the device mapper loopback target.
>
> See http://sources.redhat.com/lvm2/wiki/DMLoop for further information.
>
> It can be used as a 1:1 replacement for classic loop and should (?) probably be ready for mainline in the not too far future. (i cannot tell, but it works good for me!)
>
> Typically, you need to use dm-setup to setup device-mapper targets, but dm-setup has got support for dm-loop, so it`s as easy as 1-2-3 to replace "losetup ...." with "dmlosetup" alias for dm-setup.
>
> Feel free to test it and give feedback !
>
> regards
> Roland
>
> ps:
> dm-loop-config.patch is being linked wrong in the wiki - this is the right one: http://sources.redhat.com/lvm2/wiki/DMLoop?action=AttachFile&do=get&target=dm-loop-config.patch
>
>
>
> > 255 loop devices are insufficient? What kind of scenario do you have
> > in mind?
> >
> >
>
> Thank you very much for replying.
>
> In 1981, Bill Gates said that 64KB of memory is enough for everybody.
> And you know how much RAM do you have right now. :)
>
> Every limit is bad. The limit of 255 loop devices has been introduced
> years ago, in the times when minor device number has been limited by
> 255. Nowadays, there is no such limitation.
>
> There are many possible/reasonable uses for more than 255 loop devices.
> For example CD/ISO server. My project, Slax Linux live, is based on
> modular approach where many parts of the root filesystem are stored
> separately in compressed read-only loop files, and are mounted and
> unioned to a single root by using union fs (aufs).
>
> The question is not "Why do we need more than 255 loops?".
> The question should be "Why do we need the hardcoded 255-limit in kernel
> while there is no reason for it at all?"
>
> My patch simply removes the hardcoded limitation.
>
>
> Tomas M
> slax.org

_______________________________________________________________
SMS schreiben mit WEB.DE FreeMail - einfach, schnell und
kostenguenstig. Jetzt gleich testen! http://f.web.de/?mc=021192