Messages in this thread | | | Date | Tue, 6 Mar 2012 16:11:17 +0800 | From | Feng Tang <> | Subject | Re: TCP_STREAM performance regression on commit b3613118 |
| |
On Thu, Mar 01, 2012 at 10:07:43PM -0500, David Miller wrote: > From: Alex Shi <alex.shi@intel.com> > Date: Fri, 02 Mar 2012 10:45:17 +0800 > > > Add CC to tang feng, He is working on this issue. > > Is he? I'm pretty sure this is due to the TCP receive window growing > issue Eric Dumazet, Neal Cardwell and I are discussing in the thread > starting at: > > http://marc.info/?l=linux-netdev&m=132916352815286&w=2
Yes, probably, as we did find some clue related with the tcp_r/wmem.
Here is the regression we found: On some machines, we found there is about 10% resgression of netperf TCP-64K loopback test between 3.2 and 3.3-rc1. The exact test is: ./netperf -t TCP_STREAM -l 60 -H 127.0.0.1 -i 50,3 -I 99,5 -- -s 32768 -S 32768 -m 4096
The test machine is a 2 socket Quad Core Core 2 Duo server(2.66GHz) with 8 GB RAM. Following are the debug info (ifconfig/netstat -s/tcp_rwmem) before and after the test:
The most obvious differences I can see are: 1) 311 GB vs 241 GB from ifconfig 2) the difference of the tcp_r/wmem
Thanks, Feng
---------------------------------------------------------- Before the test (v3.2) =========================== ifconfig info eth1 Link encap:Ethernet HWaddr 00:30:48:7C:CF:72 inet addr:192.168.1.58 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::230:48ff:fe7c:cf72/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:947 errors:0 dropped:0 overruns:0 frame:0 TX packets:253 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:76573 (74.7 KiB) TX bytes:31034 (30.3 KiB) Memory:d8420000-d8440000
lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:197 errors:0 dropped:0 overruns:0 frame:0 TX packets:197 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:21827 (21.3 KiB) TX bytes:21827 (21.3 KiB)
netstat info Ip: 593 total packets received 3 with invalid addresses 0 forwarded 0 incoming packets discarded 590 incoming packets delivered 431 requests sent out Icmp: 7 ICMP messages received 0 input ICMP message failed. ICMP input histogram: destination unreachable: 7 7 ICMP messages sent 0 ICMP messages failed ICMP output histogram: destination unreachable: 7 IcmpMsg: InType3: 7 OutType3: 7 Tcp: 7 active connections openings 10 passive connection openings 0 failed connection attempts 0 connection resets received 3 connections established 371 segments received 328 segments send out 0 segments retransmited 0 bad segments received. 3 resets sent Udp: 87 packets received 7 packets to unknown port received. 0 packet receive errors 94 packets sent UdpLite: tcp_rmem 4096 87380 4194304 tcp_wmem 4096 16384 4194304 =========================
After the test (v3.2) =========================== ifconfig info eth1 Link encap:Ethernet HWaddr 00:30:48:7C:CF:72 inet addr:192.168.1.58 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::230:48ff:fe7c:cf72/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:2278 errors:0 dropped:0 overruns:0 frame:0 TX packets:690 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:174366 (170.2 KiB) TX bytes:88711 (86.6 KiB) Memory:d8420000-d8440000
lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:54845546 errors:0 dropped:0 overruns:0 frame:0 TX packets:54845546 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:334960558399 (311.9 GiB) TX bytes:334960558399 (311.9 GiB)
netstat info Ip: 54846593 total packets received 3 with invalid addresses 0 forwarded 0 incoming packets discarded 54846590 incoming packets delivered 54846212 requests sent out Icmp: 7 ICMP messages received 0 input ICMP message failed. ICMP input histogram: destination unreachable: 7 7 ICMP messages sent 0 ICMP messages failed ICMP output histogram: destination unreachable: 7 IcmpMsg: InType3: 7 OutType3: 7 Tcp: 21 active connections openings 22 passive connection openings 0 failed connection attempts 0 connection resets received 3 connections established 54846182 segments received 54846067 segments send out 0 segments retransmited 0 bad segments received. 3 resets sent Udp: 126 packets received 7 packets to unknown port received. 0 packet receive errors 134 packets sent UdpLite: tcp_rmem 4096 87380 4194304 tcp_wmem 4096 16384 4194304 =========================
Before the test (v3.3-rc1) =========================== ifconfig info eth1 Link encap:Ethernet HWaddr 00:30:48:7C:CF:72 inet addr:192.168.1.58 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::230:48ff:fe7c:cf72/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:576 errors:0 dropped:0 overruns:0 frame:0 TX packets:205 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:50045 (48.8 KiB) TX bytes:27018 (26.3 KiB) Memory:d8420000-d8440000
lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:88 errors:0 dropped:0 overruns:0 frame:0 TX packets:88 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:9613 (9.3 KiB) TX bytes:9613 (9.3 KiB)
netstat info Ip: 365 total packets received 3 with invalid addresses 0 forwarded 0 incoming packets discarded 362 incoming packets delivered 278 requests sent out Icmp: 3 ICMP messages received 0 input ICMP message failed. ICMP input histogram: destination unreachable: 3 3 ICMP messages sent 0 ICMP messages failed ICMP output histogram: destination unreachable: 3 IcmpMsg: InType3: 3 OutType3: 3 Tcp: 3 active connections openings 6 passive connection openings 0 failed connection attempts 0 connection resets received 3 connections established 226 segments received 206 segments send out 0 segments retransmited 0 bad segments received. 3 resets sent Udp: 64 packets received 3 packets to unknown port received. 0 packet receive errors 67 packets sent UdpLite: tcp_rmem 4096 87380 87380 tcp_wmem 4096 16384 65536 =========================
After the test (v3.3-rc1) =========================== ifconfig info eth1 Link encap:Ethernet HWaddr 00:30:48:7C:CF:72 inet addr:192.168.1.58 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::230:48ff:fe7c:cf72/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:1724 errors:0 dropped:0 overruns:0 frame:0 TX packets:608 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:134666 (131.5 KiB) TX bytes:79003 (77.1 KiB) Memory:d8420000-d8440000
lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:45143339 errors:0 dropped:0 overruns:0 frame:0 TX packets:45143339 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:259440765641 (241.6 GiB) TX bytes:259440765641 (241.6 GiB)
netstat info Ip: 45144169 total packets received 3 with invalid addresses 0 forwarded 0 incoming packets discarded 45144166 incoming packets delivered 45143928 requests sent out Icmp: 3 ICMP messages received 0 input ICMP message failed. ICMP input histogram: destination unreachable: 3 3 ICMP messages sent 0 ICMP messages failed ICMP output histogram: destination unreachable: 3 IcmpMsg: InType3: 3 OutType3: 3 Tcp: 16 active connections openings 17 passive connection openings 0 failed connection attempts 0 connection resets received 3 connections established 45143859 segments received 45143814 segments send out 0 segments retransmited 0 bad segments received. 3 resets sent Udp: 103 packets received 3 packets to unknown port received. 0 packet receive errors 107 packets sent UdpLite: tcp_rmem 4096 87380 87380 tcp_wmem 4096 16384 65536 =========================
| |