LLVM codegen has a significant (and good) effect on performance. https://blog.cloudera.com/blog/2013/02/inside-cloudera-impala-runtime-code-generation/
http://llvm.org/devmtg/2013-11/slides/Wanderman-Milne-Cloudera.pdf As for GCC/altivec problems, you might want to file a bug suggesting that the toolchain use a newer GCC. On Mon, Jun 13, 2016 at 7:58 AM, Nishidha Panpaliya <[email protected]> wrote: > > > Hi All, > > We wanted to know about the significance of llvm codegen feature in Impala. > For us, it is failing on power. And so far, it seems to be due to > incompatibility of LLVM 3.8 with gcc 5. > And building Impala on ppc64le with gcc 4.9 is giving lot of other errors > related to Altivec library. Even LLVM community have no plans to provide > this as a hotfix before 3.9 release. So, we wanted to know how significant > is this functionality. Can we move ahead with this one issue left? What > features are impacted or how users will be affected due to this feature. > > Thanks, > Nishidha
