Re: mlock(1)

[Neil Horman <nhorman@redhat.com>]

Jeff Garzik wrote:
> 
> How feasible is it to create an mlock(1) utility, that would allow 
> priveleged users to execute a daemon such that none of the memory the 
> daemon allocates will ever be swapped out?
> 
> ntp daemon does mlock(2) internally, for example, but IMHO this is 
> really a policy decision that could be moved out of the app.
> 
> Unfortunately I am VM-ignorant as always ;-)
> 
>     Jeff
> 

I think it would be pretty easy to do.  Since mlock(2) operates on the 
calling processes vma tree you'd need an interface to the kernel that 
let you specify a child process and an address range to lock.  Then in 
the kernel you'd need to translate the pid into task struct and 
replicate the functionality of sys_mlock without the assumption that 
current points to the task that you're modifying.  Sounds like something 
you could do pretty easy with a proc file in fact.


Neil
> 
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  *Neil Horman
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