I did some test on Linux 2.4.4 kernel w/o hardware checksum turn on by modified drivers/net/acenic.c file always let skb->ip_summed=CHECKSUM_NONE. I found hardware checksum doesn't help TCP_STREAM throughput performance. TCP STREAM TEST to 10.1.0.20 : +/-2.5% @ 99% conf. : interval Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec --------------------------------------------------------------- 131070 131070 1 60.00 6.13 131070 131070 2 60.00 12.30 131070 131070 64 60.00 284.93 131070 131070 1460 60.00 687.53 131070 131070 1500 60.00 688.32 131070 131070 3000 60.00 683.18 131070 131070 4096 60.00 681.67 131070 131070 8192 60.00 661.34 131070 131070 8193 60.00 664.68 131070 131070 16000 60.00 649.24 131070 131070 32768 60.00 651.84 131070 131070 57344 60.00 649.64 131070 131070 131000 60.00 656.26 no hareware checksum ====================== TCP STREAM TEST to 10.1.0.20 : +/-2.5% @ 99% conf. : interval Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec --------------------------------------------------------------- 131070 131070 1 60.00 6.14 131070 131070 2 60.00 12.34 131070 131070 64 60.00 284.61 131070 131070 1460 60.00 687.43 131070 131070 1500 60.00 688.82 131070 131070 3000 60.00 683.40 131070 131070 4096 60.00 686.72 131070 131070 8192 60.00 664.72 131070 131070 8193 60.00 666.82 131070 131070 16000 60.00 650.83 131070 131070 32768 60.00 652.44 131070 131070 57344 60.00 650.14 131070 131070 131000 60.00 656.00 System: 2-way netfinity boxes with 930Mhz CPUs, 1GB memory. Ethernet controller: Alteon Networks Inc. AceNIC Gigabit Ethernet Nework: Private network with Gigabit crossover cable. Test tools: netperf TCP_STREAM Kernel: Linux-2.4.4 Thanks Shirley Ma Linux Technology Center Networking Group 15450 SW Koll Parkway Beaverton, OR 97006-6063 Phone: (503) 578-7638 FAX: (503) 578-3228 - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org
