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Re: fs-independent quotas



On Thu, Oct 20, 2011 at 06:54:54PM +0200, Manuel Bouyer wrote:
> On Thu, Oct 20, 2011 at 04:39:21PM +0000, David Holland wrote:
> >  > We're talking a few MB of ram here, isn't it ? the kernel can certainly
> >  > allocate this without troubles (other subsystems do).
> > 
> > The proplib'd and XMLified complete dump for 50,000 users will
> > probably make a blob of between 10 and 20 MB. (Note: this is an
> > estimate; I haven't checked the size by trying it. It might be larger.
> > I'd be surprised if it were much smaller.)
> 
> I tested with a few 10s or users; my estimate is about 35MB for 50k users.
> 
> > 
> > I don't see why it's desirable to manifest such large objects when
> > it's easily avoidable.
> 
> We don't agree on "easily". 

FYI:  I just went around, and around, and around on this with the
configuration framework a proprietary kernel subsystem.  If you just
take the position that _any_ write to _any_ part of the data invalidates
all cursors it is not so bad.  The user application has to be coded to
deal with that, but it keeps the complexity out of the kernel.

Thor


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