Meta Has a New Linux Optimization Avoid Throttling TCP Throughput Unnecessarily
4 hours ago
- #Linux Optimization
- #Kernel Patch
- #TCP Throughput
- Meta's Linux engineering team developed a kernel patch to prevent unnecessary TCP throughput throttling.
- The patch addresses vmpressure reporting poor reclaim efficiency during high-order kswapd reclaim due to fragmentation, even with ample free memory.
- It makes vmpressure order-aware, so socket pressure is only triggered when memory allocation order is ≤ PAGE_ALLOC_COSTLY_ORDER (order 3).
- This avoids throttling TCP throughput when high-order reclaim struggles but doesn't affect net allocations.
- The patch is under review on the Linux kernel mailing list, with no specific performance numbers shared.