First off, sorry for the stutter in the spec update mail.

> The project team didn't supply a summary of the changes, so I'll be
> asking for one in a follow on.

        Summary of changes please.

>   1. This case proposes adding the following resource control:
> 
>       INTERFACE                               COMMITMENT      BINDING
>       "zone.max-swap"                          Committed        Patch
> 
>      This control will limit the swap reserved by processes and tmpfs
>      mounts within the global zone and non-global zones.  This resource
>      control serves to address the referenced RFE[6].

        There was some considerable discussion on the global zone aspect
        of this part of the proposal.  Perhaps I missed in the spec how
        the new proposal mitigates the risk of the global zone not being
        able to administer the system.

> DETAIL:
> 
>   1. "zone.max-swap" resource control.
> 
>      Limits swap consumed by user process address space mappings and
>      tmpfs mounts within a zone.

>      While a low zone.max-swap setting for the global zone can lead to
>      a difficult-to-administer global zone, the same problem exists
>      today when configuring the zone.max-lwps resource control on the
>      global zone, or when all system swap is reserved.  The zonecfg(1m)
>      enhancements detailed below will help administrators configure
>      zone.max-swap safely.

        Perhaps I misunderstood the interaction between project 0
        and zone.max-lwps in the global zone.  If a max-lwps is set
        is project 0 bound by it?
        Perhaps a short summary of the offline discussion on project 0
        and the project teams feeling that the discussions conclusions
        might not be patch qualified.  I realize the need for this project
        to have a patch binding.

>   2. "swap" and "locked" properties for zonecfg(1m) "capped_memory"
>      resource.

>      To prevent administrators from configuring a low swap limit that
>      will prevent a system from booting, zonecfg will not allow a
>      swap limit to be configured to less than:
> 
>       Global zone:     100M
>       Non-global zone: 50M.
> 
>      These numbers are based on the swap needed to boota zone after a
>      default installation.
>  
>      Also, if zone.max-swap is configured (via zonecfg(1m)) on the
>      global zone, a warning will be printed:
> 
>       global:capped-memory> set swap=200M
>       Warning: Setting capped swap on the global zone can impact
>       system availability.
> 
>      Similar warnings will be printed for setting other rctls on the
>      global zone which can affect availability, such as zone.max-lwps.

        I don't doubt that 100M and 50M are currently reasonable numbers,
        however, how will they be tracked (computed/changed) in future.

Gary..
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