5.x: how do I get a *swap*-backed /tmp via rc.conf?

[Ben Kelly]

On Monday 10 October 2005 3:49 pm, David Wolfskill wrote:
> On Mon, Oct 10, 2005 at 11:03:50AM -0400, Ben Kelly wrote:
> > On Monday 10 October 2005 10:55 am, Malcolm Kay wrote:
> > ....
> >
> > > These paramaters are used by the startup script /etc/rc.d/tmp
> > > which calls mount_md defined in /etc/rc.subr which specifically
> > > adds the _M (malloc) option to the mdmfs call.
> > >
> > > You'll need to invoke your own script (or; not so nice;
> > > edit rc.subr).
> >
> > Is there a reason not to use the ramdisk_* knobs?  This seems to work for
> > me:
> >
> > ramdisk_units="10 11"
> >
> > # tmp
> > ramdisk_10_config="-t swap -s 256m"
> > ramdisk_10_perms="1777"
> >
> > # mimedefang spool
> > ramdisk_11_config="-t swap -s 192m"
> > ramdisk_11_owner="mailnull"
> > ramdisk_11_perms="700"
> >...
>
> Well, other than the point that I'm not seeing those knobs, as

Yes.  Sorry.  I realized after I posted that those rc scripts are not hooked 
into the makefile so they will not get installed by mergemaster.  They are, 
however, in rc.conf(5) and in the src CVS tree.


> Lowell Gilbert pointed out (in response to my original message),
> the "-M" flag was moved from src/etc/rc.subr to the tmpmfs_flags
> and varmfs_flags variables in src/etc/defaults/rc.conf in HEAD (on
> 24 Aug), and that change was MFCed to RELENG_6 on 28 Aug.
>
> I filed a PR, bin/87218 about 3 hours ago, in which I requested
> that the change in question also be MFCed to RELENG_5.
>
> I have, in fact, tested the implementation of the change for RELENG_5,
> and it both allows the specification of a swap-backed /tmp (while
> preserving the default behavior) and when I put the modified RELENG_5
> box (with the swap-, rather than malloc-backed /tmp) under a superset of
> the load that crashed it yesterday, it performed without a problem.
>
> This would seem to be a Good Thing.  And I don't see a downside to the
> requested MFC for RELENG_5.

I was just trying to offer an alternative.  Also, I sent my mail this morning 
but it was held up at my outgoing mail server, so it probably looked a bit 
out of place in the conversation.

Anyway, sorry for the noise.

>
> Peace,
> david