Recompiling 31-bit non-XPLINK compute intensive applications with IBM Open XL C/C++ 2.1 for z/OS reduces execution CPU time by 13% on average compared to the same applications compiled with z/OS V2R4 XL C/C++ compiler on IBM z16 A01 *

Disclaimer:  The performance improvements are based on internal IBM laboratory measurements on IBM z16 A01. Results were obtained by taking a geomean average of reduction in execution CPU time across a set of compute intensive benchmarks that were compiled on z/OS Unix System Services with Standard C linkage in 31-bit addressing mode. The -march=z16 and -O3 compiler options were used with the IBM Open XL C/C++ 2.1 for z/OS. The -qarch=13 and -O3 compiler options were used with the z/OS V2R4 XL C/C++. All benchmarks were executed on a IBM z/OS 3.1 LPAR with 1 CP and 32GB Central Storage on IBM z16 A01. Performance results for specific applications will vary, depending on the source code, the compiler options specified, and other factors.

Recompiling 31-bit XPLINK compute intensive applications with IBM Open XL C/C++ 2.1 for z/OS reduces execution CPU time by 19% on average compared to the same applications compiled with z/OS V2R4 XL C/C++ compiler on IBM z16 A01 **

Disclaimer: The performance improvements are based on internal IBM laboratory measurements on IBM z16 A01. Results were obtained by taking a geomean average of reduction in execution CPU time across a set of compute intensive benchmarks that were compiled on z/OS Unix System Services with XPLINK linkage in 31-bit addressing mode. The -march=z16 and -O3 compiler options were used with the IBM Open XL C/C++ 2.1 for z/OS. The -qarch=13 and -O3 compiler options were used with the z/OS V2R4 XL C/C++. All benchmarks were executed on a IBM z/OS 3.1 LPAR with 1 CP and 32GB Central Storage on IBM z16 A01. Performance results for specific applications will vary, depending on the source code, the compiler options specified, and other factors.

Recompiling 64-bit compute intensive applications with IBM Open XL C/C++ 2.1 for z/OS reduces execution CPU time by 19% on average compared to the same applications compiled with z/OS V2R4 XL C/C++ compiler on IBM z16 A01 ***

Disclaimer: The performance improvements are based on internal IBM laboratory measurements on IBM z16 A01. Results were obtained by taking a geomean average of reduction in execution CPU time across a set of compute intensive benchmarks that were compiled on z/OS Unix System Services with XPLINK linkage in 64- bit addressing mode. The -march=z16 and -O3 compiler options were used with the IBM Open XL C/C++ 2.1 for z/OS. The -qarch=13 and -O3 compiler options were used with the z/OS V2R4 XL C/C++. All benchmarks were executed on a IBM z/OS 3.1 LPAR with 1 CP and 32GB Central Storage on IBM z16 A01. Performance results for specific applications will vary, depending on the source code, the compiler options specified, and other factors.