[ltp] X200s, 4 RAM 64 bit or not
D. Hugh Redelmeier
Wed, 18 Jun 2014 11:13:20 -0400 (EDT)
| From: Uwe Brauer <firstname.lastname@example.org>
| I upgraded to 4 RAM and I am running Kubuntu 10.04, trinity with PAE
| enabled. I am thinking to switch to 64 bit, but since still the majority
| of applications is 32 bit I am not sure that it is worth the effort.
10.04 is really old. I don't know what support remains (surely you
do). If you like being so far behind the bleeding edge, I wouldn't
recommend make any changes.
If you are intending to move to a new installation, I would recommend
In broad strokes: you won't notice much change. Although your
computing will probably speed up, it won't likely be enough to notice
If your / partition was 99% full, it might become 101% full :-)
But moving from 10.04 to 14.04 would increase the space requirement
much more than changing the architecture (guess).
There are a few individual programs that need more than 1G of virtual
memory. If you use any of them, you should go 64-bit. (Firefox will
eat insane amounts of memory but that doesn't mean that you should let
[boring details follow; you can skip these]
- a slight increase in the size of program code
- pointers objects take twice as much memory. The amount of data that
is made up of pointers varies by program, but usually isn't that
- C "long int" objects take twice as much memory. This usually isn't
a large consumer of memory.
- a decrease in the number of pointer and long objects that fit in the
memory caches. So some workloads become slower (rare).
The upsides are:
- increased CPU speed due to amd64 instructions (as debian and
Ubuntu call them)
+ more registers so program spends less time spilling and restoring
+ floating point is quite a bit faster
+ PAE eats a significant amount of CPU so ditching it is good
- any program that uses a lot of memory (more than 1G of virtual
memory, as I understand it) will run better
- a program can use more than 3G (I think that's the number) of
- some programs exploit the increased range of long ints (or the
increased speed of code using long long ints).
All open-source Linux programs seem to be available in AMD64. I don't
know about other stuff.