Huge page support was disabled with SA CR 728597 due to RH bug.
CR 728597: This problem is related to a possible bug in the transparent huge pages (THP) feature introduced in these operating system versions. RedHat bug 891857 has been created to track this issue. There is a huge difference between a RedHat specific bug, a bug that affects only RedHat Enterprise Linux, and a Linux (Kernel?) bug that affects other distributions. Remember that SuSE Enterprise Linux is fully supported by SAP/Sybase.
I don’t have a support contract with RedHat, so I can’t see what bug 891857 actually is.
With regard to Sybase IQ bug CR728597 and RedHat bug 891857 involving memory corruption due to Direct I/O and Transparent Huge Memory Pages, I was able to reach the RedHat engineer. Andrea Arcangeli reported the issue to the Linux kernel mailing list back in 2009. The issue was never resolved because of the complexity of the fix. https://patchwork.kernel.org/patch/11174 includes both the patch to the kernel branch of the time and the ‘repro’ C example.