8 GByte on 32-Bit Linux Kernel with PAE + mprime?

[joblack]

I've recently upgraded to 8 GByte (they are so cheap at the moment) and running them with Linux 2.6.25-1 and PAE.

I would like to upgrade to 64 Bit someday but at the moment I still have a driver which likes 32-Bit more.

Anyway, my question is what is the maximum memory for a mprime thread ... less than 4 Gbyte? Are there any other limitations? Is it actually speeding up the process with more memory?

[Kaboom]

Originally Posted by joblack

I've recently upgraded to 8 GByte (they are so cheap at the moment) and running them with Linux 2.6.25-1 and PAE.

As far as I know using PAE is going to give you a big (10-30%) performance hit, because of the overhead in memory addressing.

Originally Posted by joblack

I would like to upgrade to 64 Bit someday but at the moment I still have a driver which likes 32-Bit more.

If you plan to keep using so much memory, 64bit is the only way to go. Start searching an alternative for that driver (which one, BTW? 64bit driver support under linux is supposed to be quite solid)

Originally Posted by joblack

Anyway, my question is what is the maximum memory for a mprime thread ... less than 4 Gbyte?

2.5 GB, again AFAIK.

[joblack]

Originally Posted by Kaboom

As far as I know using PAE is going to give you a big (10-30%) performance hit, because of the overhead in memory addressing.



If you plan to keep using so much memory, 64bit is the only way to go. Start searching an alternative for that driver (which one, BTW? 64bit driver support under linux is supposed to be quite solid)



2.5 GB, again AFAIK.

The overhead for PAE isn't that hard ... 64 Bit also uses a three-level page table ... with PAE you can use up to 64 GByte RAM, only one thread can't use more than 2 GB ...

I would like to upgrade to Debian 64-Bit. The kernel is very fast changeable but is there a possibility to just upgrade to 64-Bit (with apt-get perhaps)?

[henryzz]

Originally Posted by joblack

The overhead for PAE isn't that hard ... 64 Bit also uses a three-level page table ... with PAE you can use up to 64 GByte RAM, only one thread can't use more than 2 GB ...

I would like to upgrade to Debian 64-Bit. The kernel is very fast changeable but is there a possibility to just upgrade to 64-Bit (with apt-get perhaps)?

i only use linux(ubuntu which was based on debian i think) not debian but i would be amazed if it would be possible to upgrade without a reinstall

windows has that capability but Microsoft is so big it can afford to do that sort of thing

[joblack]

Originally Posted by henryzz

i only use linux(ubuntu which was based on debian i think) not debian but i would be amazed if it would be possible to upgrade without a reinstall

windows has that capability but Microsoft is so big it can afford to do that sort of thing

Just have done so ...

Ok you can't directly upgrade but you can make it easy ...

- dpkg --get-selections > packages_installed.txt
- move everything from your root directory in a backup directory (you need knoppix or some other livecd for that (something like 'move * backup').
- reinstall without formating the partition (you need enough free space on the partition, only standard installation)

After that
- apt-get install dselect
- echo packages_installed.txt > dpkg -set-selections
- dselect (then click through until install)
- apt-get install rsync
- rsync -av -delete-after /backup/home/blabla/ /home/blabla
- copy necessary conf files from /backup/etc in /etc
- install proprietary driver (nvidia, vmware)

Normally that's it ... perhaps you need some other configuration or data files copied ... and adjust your rights/user (chown/chmod) - not always needed ...

Time: about 2 - 3 hours ...

By the way I'm not seing that mprime runs faster after that upgrade ... I'm wondering where George got the acceleration idea for 64-bits?

[lfm]

Originally Posted by joblack

By the way I'm not seing that mprime runs faster after that upgrade ... I'm wondering where George got the acceleration idea for 64-bits?

Did you forget to upgrade mprime to the 64 bit version?

[joblack]

Originally Posted by lfm

Did you forget to upgrade mprime to the 64 bit version?

Nope i've upgraded - is running on Q6600 @ 3Gh ...