--- Drat...was being more optimistic -- you're right the block_nr can be negative. Somehow thought page size could be 8K....living in future land. That just makes the limitations even closer at hand...:-(
> you keep on trying to increase the size of types without looking at > what gcc outputs in the way of code that manipulates 64-bit types.--- Maybe someone will backport some of the features of the IA-64 code generator into 'gcc'. I've been told that in some cases it's a 2.5x performance difference. If 'gcc' is generating bad code, then maybe the 'gcc' people will increase the quality of their code -- I'm sure they are just as eagerly working on gcc improvements as we are kernel improvements. When I worked on the PL/M compiler project at Intel, I know our code-optimization guy would spend endless cycles trying to get better optimization out of the code. He got great joy out of doing so. -- and that was almost 20 years ago -- and code generation has come a *long* way since then.
> seriously, why don't you just try it? see what the performance is. > see what the code size is. then come back with some numbers. and i mean > numbers, not `it doesn't feel any slower'.--- As for 'trying' it -- would anyone care if we virtualized the block_nr into a typedef? That seems like it would provide for cleaner (type-checked) code at no performance penalty and more easily allow such comparisons.
Well this is my point: if I have disks > 8T, wouldn't it be at *all* beneficial to be able to *choose* some slight performance impact and access those large disks vs. having not choice? Having it as a configurable would allow a given installation to make that choice rather than them having no choice. BTW, are block_nr's on RAID arrays subject to this limitation? > > personally, i'm going to see what the situation looks like in 5 years time > and try to solve the problem then.--- It's not the same, but SGI has had customers for over 3 years using >2T *files*. The point I'm looking at is if the P-X series gets developed enough, and someone is using a 4-16P system, a corp user might be approaching that limit today or tomorrow. Joe User, might not for 5 years, but that's what the configurability is about. Keep linux usable for both ends of the scale -- "I love scalability"....
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