On 13/03/2010 15:55, John A. Sullivan III wrote:
> <snip>
> That's interesting. I'd like to pursue this a bit, if I may because
> that's what I originally expected in VServer but I don't think it is
> what I am seeing. For example, we are running many vservers with KDE
> desktops. I was expecting that since they are all looking at the same
> hardlinked X and KDE files,memory usage would be minimal. However, we
> see each vserver consuming between 500MB and 1GB of RAM (from
> vserver-stat).
>
My (very limited) understanding is that the memory reductions come from
the kernel sharing only the static parts of the libraries - I would have
thought that user data at run time usually dominated the memory usage of
most applications though? Usually the binaries and libraries are of
negligible size compared with the amount of ram the application uses?
I guess the max benefits come from server apps which are used
identically in multiple VMs and the app particular focuses on minimising
runtime memory allocation
You mention that Firefox is ballooning memory - this is also my
observation on Windows/OSX on the desktop and given all the memory is
unique to building/parsing/caching individual web pages *per browser*,
then I can't see any way that the vhashify is going to help here.
Firefox also seems to "leak"memory badly for me (for a certain
definition of leak) and I find I must restart it every few days (usually
its obvious because it reaches the point that where it's very sluggish
to open tabs and for me it slows down heavily once it hits 500MB-1GB of
ram used - restarting it usually gets memory usage down to 100-200MB...
(with the same 15-30+ tabs open)
Another trick I found on FF is that it seems to get sluggish opening new
tabs - I traced this to two things, one is optimising the sqlite dbs,
the second is that *I* end up with a massive database of form fields
that it's remembering and for whatever reason once this gets big it
leads to HUGE slowdowns opening new pages and lots of microfreezes for a
few secs. Clearing the cached form values (and all your remembered
passwords...) gets everything back to lightning fast speeds
So basically I can't see that the vhashify can save more than the size
of the libraries that have been hashified (and are in use), which is
likely to be only a few hundred MB on most server installations (perhaps
a lot less?). Perhaps not to be sneezed at, but perhaps not enough for
some requirements?
Good luck
Ed W
Received on Mon Mar 15 18:16:44 2010