On Tue, 10 Jan 2006, Jeffrey Hundstad wrote:
On 1/10/06, Andi Kleen <[email protected]> wrote:
On Tuesday 10 January 2006 03:12, Jesper Juhl wrote:
...
Ah - how legacy.
Yeah, but since my distro of choice is 32bit only and I don't much
feel like porting it myself or using an unofficial port (slamd64) I'm
sticking with a 32bit userspace. And as long as userspace is pure
32bit there doesn't seem to be much point in building a 64bit kernel.
And I only have 2GB of RAM, so I don't have a use for the larger 64bit
address space.
I also don't run any apps that do a lot of math on >32bit numbers, so
there's not much gain there either.
I guess I would bennefit from the extra GPR's, but then I would at the
same time loose a bit by all pointers being 64bit - both lose some
disk space due to larger binaries and I'd have increased memory use
and less efficient L1/L2 cache use.
I don't think there would actually be much gain for me in switching to
a 64bit kernel with a 64bit userspace atm.
But if I'm wrong I'd of course love to hear about it :)
Has anyone done any actual benchmark tests that show 64-bit vs 32-bit
environments/distributions with Athlon64 processors. If so, I love to see
the results. I too elected to stick with 32-bit, using the same
reasoning/guessing above.
remember that benchmarks are all dependant on your workload, but on some
of my workloads (lots of fork-based network services) I've seen a 50%+
increase by switching from a 32 bit to 64 bit kernel with 32 bit
userspace, and a further 50%+ increase by switching to a 64 bit userspace.
remember that on amd64 systems 64 bit programs have access to twice as
many registers as 32 bit programs. This can be more of a win then the
extra pointer size is a loss.
David Lang
--
There are two ways of constructing a software design. One way is to make it so simple that there are obviously no deficiencies. And the other way is to make it so complicated that there are no obvious deficiencies.
-- C.A.R. Hoare
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
