Category Archives: Assembler

RxRandom Revisited — Metal C

Continuing the Writing a Rexx Function in C and the follow-on Updated RxRandom External Rexx Function (in C) discussion, can I convert RxRandom to Metal C? I originally worked on writing Rexx external function in C using the System Programmer C facility; this was before Metal C existed. There should be some performance benefit to… Read More »

Using Metal C to Learn Assembler Techniques

By comparing the output from the XL C/C++ Compiler that is generated for a sample piece of C code and varying the ARCHITECTURE and TUNE compiler options, we can both learn some new assembler opcodes for newer hardware and also learn some optimization techniques. Currently (September 2013), the ARCHITECTURE value can vary from 0 to… Read More »

Is it time for a Syncpoint?

When you are sharing an online database with batch update jobs you don’t want batch jobs to affect online response time.  One thing that invariably delays online transactions are batch database locks.  If the batch job doesn’t take enough syncpoints, more and more of the database will be locked as the job runs. The best… Read More »

Use C Runtime Functions in Assembler

Assembler coding has it’s role to fill.  There are a lot of system services that are only available to assembler programs and when performance is key there is often nothing better.  That being said, when you are coding in assembler you want to focus on the problem at hand and not spend a lot of… Read More »