labath added a comment. Thanks for the review.
In D78489#1998060 <https://reviews.llvm.org/D78489#1998060>, @clayborg wrote: > In D78489#1996834 <https://reviews.llvm.org/D78489#1996834>, @labath wrote: > > > I've done a similar benchmark to the last one, but measured memory usage > > ("RssAnon" as reported by linux). One notable difference is that I > > > > Currently (information retrieved from DW_AT_ranges) we use about ~330 MB of > > memory. If I switch to dwarf dies as the source, the memory goes all the > > way to 2890 MB. This number is suspiciously large -- it either means that > > our die freeing is not working properly, or that glibc is very bad at > > releasing memory back to the OS. Given the magnitude of the increase, i > > think it's a little bit of both. With line tables as the source the memory > > usage is 706 MB. It's an increase from 330, but definitely smaller than 2.8 > > GB. (the number 330 is kind of misleading here since we're not considering > > removing that option -- it will always be used if it is available). > > > Since we mmap in the entire DWARF, I am not surprised by taking up new memory > because we touch those pages and won't get those back. If you remove the DIE > freeing code, I will bet you see much more memory used. We definitely free > the memory for the DIEs and give that back, so I would be willing to bet the > increase you are seeing is from mmap loading pages in that we touch. I don't think it's as simple as that. "RssAnon" should not include file-backed memory (which why I chose to measure it). According to `man proc`: * RssAnon: Size of resident anonymous memory. (since Linux 4.5). * RssFile: Size of resident file mappings. (since Linux 4.5). I also don't think it's as simple as not freeing the DIE memory at all. There has to be some more complex interaction going on. If I had more time, I would be very interested in learning what it is, but for now I'll contend myself with "it's not a problem of this patch". Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D78489/new/ https://reviews.llvm.org/D78489 _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
