Re: "big" machines running Debian?
lsorense@csclub.uwaterloo.ca (Lennart Sorensen) writes:
> On Wed, Feb 25, 2009 at 04:07:54PM +0100, Goswin von Brederlow wrote:
>> I think the limit is 1024 cores. Or was that fixed to allow more?
>
> I think people are working on that, but not too many machines need
> that yet. Most machines with that many cores are clusters and hence
> run multiple linux instances.
>
>> As for ram that really is a cpu/architecture limit and you won't be
>> able to find a motherboard that supports as much ram as the cpu(s)
>> could handle.
>
> I can't remember if the current amd64/x86_64 architecture limit is 40bit
> or 44bit of physical memory space. Fairly decent chunk of ram either way,
> if you can fit it into the system in the first place.
cat /proc/cpuinfo
address sizes : 40 bits physical, 48 bits virtual
which means 1TiB of ram. Good luck finding a board for that.
>> More than 1TB on disk? Doh. 1TB fits on a single disk. Anything up to
>> 16 TB is quite trivial. Beyond that you start to hit the limit on
>> filesystem size with ext3 and have to use xfs or ext4 or something. Or
>> you have to partition the space iinto 16TB chunks. Also > 16 disks
>> requires a big enough case or external storage. For that I would look
>> into external enclosures with SAS connector. Don't use SCSI or FC.
>
> Well at 2TB you have to switch from DOS style partition tables to GPT,
> which requires the use of grub2 rather than lilo or grub, but works
> fine otherwise.
Nah. Just needs /boot to be below 2TiB. The GPT has a fake MS-Dos
table inside that grub can use and lilo only looks at the block
addresses anyway.
MfG
Goswin
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