On 14 June 2016 at 06:58, Nishidha Panpaliya <[email protected]> wrote:
> > > Hi Jim, > > Thank you for your reply. Links that you sent us helped to understand the > impact. But I believe, if it is only performance related and not blocking > any Impala's feature, we can still live with that issue if it is just not > possible to fix either for LLVM community or for us. Please correct me if I > misunderstood. > It depends what you mean by "we", and "live" :) Are you planning to contribute your changes back to the Apache Impala project? If so, we can discuss omitting codegen support on that issue, preferably on a JIRA. Henry > > On another note, I could fix gcc 4.9.3 issue with ALTIVEC and could build > Impala with it on power. And llvm-codegen test passed on it. So, if > everything else works with this setup, we would rather go with gcc 4.9.3 on > power for Impala. > > Thanks again for helping us always. > > Regards, > Nishidha > > ----- Forwarded by Nishidha Panpaliya/Austin/Contr/IBM on 06/14/2016 07:17 > PM ----- > > From: Sudarshan Jagadale/Austin/Contr/IBM > To: Nishidha Panpaliya/Austin/Contr/IBM@IBMUS > Date: 06/14/2016 10:35 AM > Subject: Fw: LLVM codegen functionality > > > FYI > Thanks and Regards > Sudarshan Jagadale > Power Open Source Solutions > ----- Forwarded by Sudarshan Jagadale/Austin/Contr/IBM on 06/14/2016 10:34 > AM ----- > > From: Jim Apple <[email protected]> > To: [email protected] > Cc: Silvius Rus <[email protected]>, Manish > Patil/Austin/Contr/IBM@IBMUS, Sudarshan > Jagadale/Austin/Contr/IBM@IBMUS, Valencia > Serrao/Austin/Contr/IBM@IBMUS, Anup > Halarnkar/Austin/Contr/IBM@IBMUS > Date: 06/13/2016 08:33 PM > Subject: Re: LLVM codegen functionality > > > > 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 > > > -- Henry Robinson Software Engineer Cloudera 415-994-6679
