Hi Jacob, Thanks for the review, I tested this patch previously for 4kb page size systems. The throughput improvement is around 10 to 15%. Also sligthly better memory utilization as for typical 1500 MTU size we are able to fit 2 Rx buffer in a single 4kb page as compared to 1 per page previously.
Thanks Dipayaan Roy On Mon, Jul 21, 2025 at 04:51:10PM -0700, Jacob Keller wrote: > > > On 7/21/2025 3:14 AM, Dipayaan Roy wrote: > > This patch enhances RX buffer handling in the mana driver by allocating > > pages from a page pool and slicing them into MTU-sized fragments, rather > > than dedicating a full page per packet. This approach is especially > > beneficial on systems with 64KB page sizes. > > > > Key improvements: > > > > - Proper integration of page pool for RX buffer allocations. > > - MTU-sized buffer slicing to improve memory utilization. > > - Reduce overall per Rx queue memory footprint. > > - Automatic fallback to full-page buffers when: > > * Jumbo frames are enabled (MTU > PAGE_SIZE / 2). > > * The XDP path is active, to avoid complexities with fragment reuse. > > - Removal of redundant pre-allocated RX buffers used in scenarios like MTU > > changes, ensuring consistency in RX buffer allocation. > > > > Testing on VMs with 64KB pages shows around 200% throughput improvement. > > Memory efficiency is significantly improved due to reduced wastage in page > > allocations. Example: We are now able to fit 35 Rx buffers in a single 64KB > > page for MTU size of 1500, instead of 1 Rx buffer per page previously. > > > Nice to see such improvements while also reducing the overall driver > code footprint! > > Do you happen to have numbers on some of the smaller page sizes? I'm not > sure how common 64KB is, but it seems like this would still be quite > beneficial even if you had 4K or 8K pages when operating at 1500 MTU. > > Reviewed-by: Jacob Keller <[email protected]>
