Les Mikesell wrote: > On 8/31/2010 11:04 AM, Stephen Harris wrote: > >>> Stack size was only a problem for the 32 bit OS and not 64 bit. If one >>> is dealing with a terabyte or more of data, I don't see them using a 32 bit >>> OS. >>> >> Huh; >> >> /dev/mapper/Raid5-Media >> 3.3T 3.1T 216G 94% /Media >> >> % uname -sr >> Linux 2.6.18-194.3.1.el5PAE >> >> >>> I really don't see any really good reasons for using anything but 64 bit >>> any more, if the hardware supports it. >>> >> I don't find the RedHat 32bit/64bit split to be as clean as it should be >> (definitely messy when compared to Solaris). When it comes to needing to >> install 32bit and 64bit versions of the same program (eg perl 'cos you >> only have 32bit binary libraries from vendors) it gets a little hairy. >> And then Oracle really starts to get antsy on you. >> >> As a result, when I first installed CentOS 5 I stuck with 32bit because >> it was more stable. After all, my memory footprint is only around >> 200Mb on this machine; the rest is cache! >> > > The kernel and user apps are pretty much different things. You can run > a 64-bit kernel and 32-bit apps if you want. But the issue with a > 32-bit kernel besides what it can provide as a process address space is > that at least the way RH and CentOS build it, it uses 4k stacks which > may not be enough for some xfs operations. > > Are you saying here that I can take a system that has been installed from a 32 bit distribution and simply replace the kernel with a 64 bit kernel? Thanks, Nataraj