Michael Smith has posted comments on this change. ( http://gerrit.cloudera.org:8080/20692 )
Change subject: IMPALA-11542: Implement pre-allocation in LLVM memory manager ...................................................................... Patch Set 7: (2 comments) http://gerrit.cloudera.org:8080/#/c/20692/4/be/src/codegen/mcjit-mem-mgr.cc File be/src/codegen/mcjit-mem-mgr.cc: http://gerrit.cloudera.org:8080/#/c/20692/4/be/src/codegen/mcjit-mem-mgr.cc@49 PS4, Line 49: > Do you know what is the role of alignment here and what values can we expec Alignment is probably smaller than page size, and must be a power of 2. I believe page size is also a power of 2. We align on both following a slightly silly algorithm because allocateSection actually overallocates memory (to ensure the starting address can be aligned correctly). Read the comments in requiredPageSize. http://gerrit.cloudera.org:8080/#/c/20692/4/be/src/codegen/mcjit-mem-mgr.cc@143 PS4, Line 143: : > What comes after this seems essentially dead code, as needsToReserveAllocat It's slightly changed now. I made changes that match what I'll likely submit upstream to LLVM, where I think whether to reserve allocation space would be a constructor arg. -- To view, visit http://gerrit.cloudera.org:8080/20692 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I9f224edcdbdcb05fce663c18b4a5f03c8e985675 Gerrit-Change-Number: 20692 Gerrit-PatchSet: 7 Gerrit-Owner: Michael Smith <michael.sm...@cloudera.com> Gerrit-Reviewer: Csaba Ringhofer <csringho...@cloudera.com> Gerrit-Reviewer: Daniel Becker <daniel.bec...@cloudera.com> Gerrit-Reviewer: Impala Public Jenkins <impala-public-jenk...@cloudera.com> Gerrit-Reviewer: Joe McDonnell <joemcdonn...@cloudera.com> Gerrit-Reviewer: Michael Smith <michael.sm...@cloudera.com> Gerrit-Reviewer: Yida Wu <wydbaggio...@gmail.com> Gerrit-Comment-Date: Fri, 10 Nov 2023 16:34:24 +0000 Gerrit-HasComments: Yes
