add more swap to jail within a jail

[John Nielsen]

On Mar 26, 2013, at 5:55 AM, Nicolas de Bari Embriz Garcia Rojas <nbari at inbox.im> wrote:

> Hi, how can I add more swap space within a jail ?
> 
> I have a jail  with limited resources via rctl with somethiing like:
> 
> jail:myjail:maxproc:deny=50
> jail:myjail:memoryuse:deny=512M
> jail:myjail:swapuse:deny=512M
> 
> But I want to know it it is  possible to add jail disk space to
> increment the swap ?
> 
> I am  trying to compile gearmand/boots-libs but I can't since eats to
> much memory.
> 
> An initial solution is to add the swap on the host, but is there a way
> to do it within the jail so that the (root user/admin) doesn't have to
> bother the host admin.

I jail does not have its own virtual memory subsystem so I doubt this is possible or advisable. And even if the host admin configures it, swap space should NOT be directly readable from a jail as it will likely contain data from external processes which the jail should not have access to.

JN