Friday, March 14, 2008

Interview question

During interviews one of the questions I ask is: "What is the basic difference between 32-bit and 64-bit application?". The obvious one is the available address space for an application. The other one is performance - more details here.

btw: it is really scary how few sys admins know the answer to the question, even if just the address space part...

2 comments:

Anonymous said...

When the Opterons initially came out, and I could finally get my hands one, I was pleasantly surprised to see a 20% speed improvement going from -m32 to -m64 on the same computer.

vnull said...

IMHO there are situations in which IA 64-bit would have worse performance than 32-bit (many ctx switches and larger set of registers).