Fonzie, There's are two different things involved when talking about 64-bit. First is whether individual applications are running as 64-bit. If you have a 64-bit processor, then any application that is 64-bit capable will run 64-bit. 32-bit applications continue running as 32- bit. This happens automatically, and it depends on whether the individual program supports 64-bit.
An application that is 64-bit can use more than 4GB of RAM, and also 64-bit Intel apps tend to perform better than 32-bit Intel apps. On SnowLeopard, just about every application that ships with SnowLeopard is 64-bit. You can check this yourself by launching Activity Monitor which is in the Utilities folder. Activity Monitor has a table of running programs. The "Kind" column in the table will say "Intel (64-bit)" for programs running in 64-bit, and just plain "Intel" for programs running in 32-bit. Everything that I described above happens without you doing a thing. If an app supports running as 64-bit, it does so automatically. If an app only supports 32-bit, it runs 32-bit automatically. The second thing involved is whether the Mac OS X kernel itself is running as 64-bit or 32-bit. According to this AppleCare article (http://support.apple.com/kb/TS2937 ): "Third-party software (such as a virtualization engine) or hardware (such as a PCIe card) that relies on a kernel extension which was compatible with Mac OS X Server v10.5 may not work on servers that use the 64-bit kernel in Mac OS X Server v10.6." My guess is that there are enough kernel extensions out there that are not yet 64-bit, that it made sense to keep the kernel running in 32- bit, to prevent lots of users from having things stop working. Note that regardless of whether the low-level kernel code is running at 32 or 64 bit, you still get the advantages of applications running as 64-bit. So, that's the long answer to your question. The short answer to your question: "Should I worry about booting into 64 bit mode?" is no, you shouldn't worry about it. You are already, automatically, getting all the 64-bit benefits that are described for SnowLeopard here: http://www.apple.com/macosx/technology. -James ---------------- James Dempsey demp...@mac.com On Aug 30, 2009, at 8:51 AM, Fonzie wrote: > > Hi everyone, I hope your morning/afternoon, or whatever time it is > goes well. > > I noticed that.... Snow Leopard boots in 32 bit mode. > > I check the list of supported 64 bit Macs, and mine is surely on the > list. > > Should I worry about booting into 64 bit mode? > > If so, how would you make it so that it boots into 64 bit mode every > time, and not one that you would have to tell it too. > > Right now, the only way I know of to boot into 64 bit mode, is to > start up, and hold 6 and 4 keys down. > > Take care. > > Fonzie > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "MacVisionaries" group. To post to this group, send email to macvisionaries@googlegroups.com To unsubscribe from this group, send email to macvisionaries+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/macvisionaries?hl=en -~----------~----~----~----~------~----~------~--~---
