Bug 16490

Summary: glibc 2.43 allocates much more memory than glibc 2.39
Product: [Build System, Metadata & Runtime] OE-Core Reporter: Etienne Cordonnier <ecordonnier>
Component: coreAssignee: Unassigned <unassigned>
Status: NEW --- QA Contact:
Severity: major    
Priority: Undecided CC: meta.mr.watcher, meta.watcher
Version: 6.0.3   
Target Milestone: 0.0.0   
Hardware: ARM   
OS: arm64   
Whiteboard:
OS type for building Yocto: --- Type of Regression: ---
Verified: Documentation change: No (bug/feature does not impact docs)

Description Etienne Cordonnier 2026-11-05 12:48:37 UTC 
We noticed this critical regression while updating from scarthgap 5.0.20 to wrynose 6.0.3:

glibc 2.43 malloc allocations on aarch64 are massively bigger than on glibc 2.39. We have reported findings at https://sourceware.org/bugzilla/show_bug.cgi?id=34081 which is the upstream bug.

We compared the same image based on scarthgap 5.0.20 with only glibc changed. These are system-wide readings from one cold boot per configuration, averaged
over 55-180 s after boot at idle:

                          2.39     2.43
  AnonPages (MiB)          465     1105
  AnonHugePages (MiB)        0      743
  MemAvailable (MiB)      1850     1214
  Swap-out since boot (MiB)  0      385