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The new index is constructed so > that this should be easy to do, but the series is long enough, and > complicated enough, that I did not want to add this on. (It's not > enough to update the writer -- the reader must also be updated, and > one must decide how much backward compatibility to keep.) > > Why write a new indexer, rather than simply fix the psymtab reader? I > have tried that multiple times over the years, without success. I > believe that parallelism is the key to increased performance, and this > is just too hard to retrofit onto the existing reader. > > This series starts with a number of refactorings. I've already landed > a number of these, but the ones that remain are specific to this > series, so I didn't try to submit them separately. > > The new code is also broken into separate patches for simpler review. > > Some of the performance gains are actually just an illusion -- some > work is moved to the background, and if the main part of gdb needs the > information, it will once again appear to be slow. However, this is > still an improvement for some common situations, for example simply > starting gdb on a large program. My preferred long-term fix here > would be to replace DWARF with something that's less terrible for > reading; but failing that we can maybe eke out some small incremental > gains through further micro-optimization, or by farming out this > scanning to something like debuginfod. > > I've regression tested each patch in this series. Only the patch to > enable the new indexer is intended to affect operation at all. > > Tom Tom, Given the lack of response to our reiterated pings, would you prefer that we get rid of the partial symbol table in the CTF reader as well? Thanks.