DEVFS in a chroot?

[Poul-Henning Kamp]

In message <20040430.075448.70646001.imp at bsdimp.com>, "M. Warner Losh" writes:
>In message: <6695.1083331489 at critter.freebsd.dk>
>            "Poul-Henning Kamp" <phk at phk.freebsd.dk> writes:
>: In message <20040430.070341.26991317.imp at bsdimp.com>, "M. Warner Losh" writes:
>: >In message: <5473.1083327210 at critter.freebsd.dk>
>: >            "Poul-Henning Kamp" <phk at phk.freebsd.dk> writes:
>: >: >Should I mount /var/chroot/dev as type devfs?
>: >: 
>: >: Yes:
>: >: 
>: >: 	mount -t devfs randomargument	/var/chroot/dev
>: >
>: >What if I have hundreds of these chroots?  We build our product inside
>: >a chroot right now and I'm worried what the overhead of
>: >mounting/unmounting this for every build would be...
>: 
>: As far as I recall, our mountlist handling is not optimised for
>: hundreds of simultaneous mountpoints: we basically walk the list.
>: That said, I belive we only do so during the actual mount/unmount
>: operations, so I do not think there is a performance issue as such.
>
>Would the performance issues be mitigated by mounting/unmounting devfs
>all the time?  Eg, only mount it while it is actively being used?

I think you would actually make it worse that way...

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.