Running 32-Bit Applications On A 64-Bit Linux Os; Pci Express Graphics On 64-Bit Workstations - HP xw3400 User Manual

Running 32-bit Applications on a 64-bit Linux OS

In order to run 32-bit applications on a 64-bit Linux OS, the 32-bit runtime environment is needed in
addition to the application itself. Many applications use a variety of shared libraries including core
Linux support libraries such as glib and math libraries, X window libraries such as Xlib and Xext, and
toolkits such as Qt. Red Hat and the other Linux distributions provide libraries and runtime support for
some of the 32-bit packages that are available in their 32-bit version of the OS. This is typically not
all of the 32-bit packages and thus some applications may not have all the 32-bit shared libraries and
runtime support that are needed for the application to run.
Because some of the files in the 32-bit runtime support conflict with 64-bit runtime files, the 32-bit
packages cannot be blindly installed on top of the 64-bit OS. To run 32-bit applications that require
more runtime support than provided by Red Hat or the other Linux distribution being used, the needed
files must be in place on the system running the application. The ldd command will enumerate all of
the static library references in the application. Once the missing libraries are discovered, simply
follow these steps to safely add the 32-bit rpms that contain these missing libraries:
rpm2cpio <32-bit rpm>
rpm -i --force <64-bit rpm>
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:<32-bitpath>
where <32-bitpath> is something like /32bitlibs and <32-bit rpm> is the name of the 32 bit rpm.
Over time, the Linux 64-bit distributions have already improved and will hopefully get even better at
delivering 32-bit runtime environment.

PCI Express Graphics on 64-bit Workstations

The new workstations all support PCI Express x16 graphics cards instead of AGP-8x graphics cards
and the HP xw9300 Workstation supports 2 of these PCI Express x16 graphics cards. Initial graphics
support for 64-bit Linux consists of only NVIDIA PCI Express cards and the 280 NVS PCI card. ATI
support will come in the future, once the ATI Linux 64-bit drivers for their PCI Express cards are tested
and integrated into HP's Installer Kit. On Red Hat releases prior to RHEL3 Update 5 and RHEL 4
Update 1, the 64-bit NVIDIA driver requires a configuration change to the kernel in order to expand
the size of the software TLB buffer space. The /boot/grub/grub.conf file MUST BE CHANGED to add
the parameter "swiotlb=16384" to the end of the lines that begin with "kernel." This was done
automatically by HP's graphics driver rpms, but must be done manually if the NVIDIA "_run" scripts
were used to install NVIDIA drivers.
Building and using graphics-intensive 64-bit applications should be similar to other 64-bit apps except
for the dependency on graphics middleware and libraries. Application developers will need to make
sure that all libraries that are used to build the application are available in 64-bit versions. Although
HP delivers the 32-bit OpenGL libraries (from the graphics vendors) needed to run 32-bit graphics
apps on the 64-bit version of the OS, the 32-bit runtime issues mentioned above may cause problems
in the graphics space also. We have found that the 64-bit graphics libraries have about the same
performance as the 32-bit libraries.
> <32-bitpath>
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