On Tue, Jul 21, 2026 at 11:02:34AM +0200, Morten Brørup wrote: > The mempool cache size is configurable. > > The application developer should configure it to strike a balance > between the two performance parameters: > > - Throughput: Large mempool cache reduces the number of backend > transfers. > > - Latency: Large mempool cache causes latency spikes (CPU cache misses) > when transferring objects from/to cold backend memory. > > Since 26.11 is an ABI break release, perhaps we can reconsider the option to have the "keep" value configurable for the mempool caches, i.e. for random alloc/free's set it to 50% like you have, or 25% as proposed by my patch, while for pipeline apps it should be set to 0%. Rather than us constantly arguing^H^H^H discussing what the value should be, we can make it tunable for the developer?
As an alternative version of that proposal, we can simplify and just have a couple of predefined simple profiles for 2 or 3 values, one for pipeline apps, and one or two for run-to-completion, rather than exposing the whole range of possibilities to the user. /Bruce
