Re: [PATCH v4 00/23] perf symbol: Sorted arrays, DSO-owned lifetimes, and memory shrinking

[Namhyung Kim <namhyung@kernel.org>]

Hello,

On Fri, Nov 13, 2026 at 09:25:34PM -0800, Alireza Haghdoost wrote:
> On Fri, Nov 13, 2026 at 9:17 AM Ian Rogers <irogers@google.com> wrote:
> >
> > When profiling large binaries or long-running workloads with many DSOs and
> > threads, symbol and DSO tables frequently dominate perf's memory footprint
> > and startup latency.
> [...]
> 
> Hi Ian,
> 
> Thanks for v4, and for pulling the three fixes out; they are in
> perf-tools-next now. I posted v7 of the lazy loading series on current
> perf-tools-next. I apologize for the late turnover.
> 
> Lazy loading stays opt-in there for now (just don't have confidence
> yet to make it default, see
> my reply on v6 4/5). From reading v4, the two series overlap in three places:
> 
> - Both use bit 14 of the symbol flags: SYMBOL_FLAG_ANNOTATED in 11/23
>   and SYMBOL_FLAG_LAZY_NAME in v7 3/4. Bit 15 is the last free one.
> - 18/23 replaces the rb-tree. v7 3/4 walks it in two places during
>   loading: the alias name loading before symbols__fixup_duplicate(),
>   and the check that skips a .dynsym entry copying a lazy .symtab
>   symbol. Both would become walks over the sorted array.
> - 15/23 defers elf_sym__name() in dso__load_sym_internal(), the loop
>   where v7 records the name offset instead of the name. Both want the
>   name as late as possible, so this looks mechanical.
> 
> Namhyung, which order do you prefer? lazy loading v7 is four patches;
> if Ian's v4 goes
> first, I'll rebase v7 on it.

Thanks for understanding.  I have no preference and will merge whatever
ready first.  It seems your v7 needs some updates.  I think I'll merge
some of Ian's patches first but it seems that's not part of the
conflicts.  Let me take a look. :)

Thanks,
Namhyung