During discussions on RHEL-3007, Paulo Andrade and I realized that free does not batch deallocations. Batching deallocations addresses Paulo's queuing policy concerns and should also help with performance because the arena locking cost is amortized across multiple free calls. This becomes more important after fastbin removal, which is under discussion upstream.

Patches implementing batching have been posted upstream:

• Re: [PATCH 0/9] malloc: Remove fastbins

Once these patches are accepted upstream, we should consider if we want to backport them into RHEL 10, along with all the other malloc performance improvements. This ticket serves as a reminder for this evaluation.