I re-ran the splice ns->host test using splice, and it works flawlessly. It seems like Stefano's fix solved the problem. /jon [ 5] 90.00-91.00 sec 4.06 GBytes 34.9 Gbits/sec [ 5] 91.00-92.00 sec 4.05 GBytes 34.8 Gbits/sec [ 5] 92.00-93.00 sec 4.04 GBytes 34.7 Gbits/sec [ 5] 93.00-94.00 sec 3.93 GBytes 33.8 Gbits/sec [ 5] 94.00-95.00 sec 3.92 GBytes 33.6 Gbits/sec [ 5] 95.00-96.00 sec 3.95 GBytes 33.9 Gbits/sec [ 5] 96.00-97.00 sec 3.91 GBytes 33.6 Gbits/sec [ 5] 97.00-98.00 sec 3.92 GBytes 33.7 Gbits/sec [ 5] 98.00-99.00 sec 3.67 GBytes 31.5 Gbits/sec [ 5] 99.00-100.00 sec 3.64 GBytes 31.3 Gbits/sec [ 5] 100.00-100.00 sec 1.88 MBytes 35.0 Gbits/sec - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate [ 5] 0.00-100.00 sec 389 GBytes 33.4 Gbits/sec receiver ----------------------------------------------------------- Server listening on 5201 (test #2) -----------------------------------------------------------