Oliver Fromme <olli_at_lurza.secnetix.de> writes: > It's a common mistake to assume that amd64 only makes sense > if you have >= 4GB RAM. There are several reasons why it > might be useful to switch from i386 to amd64: > > - Most programs (though not all) will run faster, because > in amd64 mode there are twice as many general-purpose > registers, giving compilers much better opportunities > for optimizations and caching of values, and reducing > slow memory accesses. "twice as many" is an understatement. AMD64 has 16 GPRs vs i386's 8 if you consider BP, SI, DI and SP as GPRs (as the AMD and Intel literature does); in practical terms the score is 12 to 4. > - Some applications might benefit from a larger virtual > address space > 4 GB. (Note that this is not related > to the amount of physical RAM!) For instance, Varnish maps its entire storage into memory, and will benefit greatly from the increased address space. > In practice there's (almost) only one reason not to run > FreeBSD/amd64 on amd64-capable hardware: If you depend > on a certain piece of software which is known not to run > correctly in 64bit mode. Fortunately those are not many. The only one I can think of (for a desktop) is the Flash plugin. DES -- Dag-Erling Smørgrav - des_at_des.noReceived on Wed Jun 06 2007 - 08:47:58 UTC
This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:39:11 UTC