[mythtv-users] Any advantage going to 64 bit?

[Alex Butcher]

On Thu, 10 Mar 2011, Gabe Rubin wrote:

> My combined FE/BE uses a Sempron 140 CPU, which I understand is
> capable of 64 bit computing.  I believe I am running it with a 32 bit
> kernel, which I base off the following (but I could be wrong):
> [root at localhost ~]# uname -r
> 2.6.35.10-74.fc14.i686
> [root at localhost ~]# uname -m
> i686

Correct.

> Is there an advantage to me running in 64 bit?

The 64 bit instruction set adds some new registers and a few new
instructions, which can improve performance.  On the other hand, pointers
are twice the length and take longer to fetch from memory, so it might all
average out to little advantage.  Also, on a system admin note, some
applications (notably Adobe's Flash browser plugin) aren't released (as
often) as 64 bit binaries.  And, of course, processes can grow to >4GB in
size (which is probably more useful for large database servers and
image/video editors than much else).

> If so, what would I need to do to accomplish this (on a Fedora 14 system
> using yum with atrpms as my primary install method)?  Is it as simple as
> yum install <correct kernel> and then yum update to get all my programs
> upgraded to the 64 bit versions as appropriate?

You might be able to get away with that, but ISTR the only supported way
would be to reinstall from 64 bit install media.

My take is that, on balance, it probably isn't worth you switching. OTOH, if
one is performing a new install on 64-bit capable hardware, it's probably
worthwhile using it.

> Thanks

HTH,
Alex