Evaluation of x32-ABI in the Context of LHC Applications

The application binary interface x32 (x32-ABI) was introduced in Linux kernel 3.4 and is based on the x64 instruction set. Instead of 64-bit it uses 32-bit as size for pointers and C-data type long, reducing consequently memory overhead. As several LHC applications, especially reconstruction and analysis software, suffer memory problems, since the change from 32- to 64-bit, this binary interface has been evaluated. This paper shows that in most of the applications, used at CERN, the memory overhead can be reduced between 3 % and 35 % and the corresponding difference in CPU-time can be improved up to 30 %.