On 07/11/2012 08:11 AM, Eric Dumazet wrote:
Some bench results about the choice of 128KB being the default value:
What were the starting/baseline figures?
Tests using a single TCP flow.
Tests on 10Gbit links :
echo 16384 >/proc/sys/net/ipv4/tcp_limit_output_bytes
OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.99.2
(192.168.99.2) port 0 AF_INET
tcpi_rto 201000 tcpi_ato 0 tcpi_pmtu 1500 tcpi_rcv_ssthresh 14600
tcpi_rtt 1875 tcpi_rttvar 750 tcpi_snd_ssthresh 16 tpci_snd_cwnd 79
tcpi_reordering 53 tcpi_total_retrans 0
Local Local Local Elapsed Throughput Throughput Local Local
Remote Remote Local Remote Service
Send Socket Send Socket Send Time Units CPU CPU CPU
CPU Service Service Demand
Size Size Size (sec) Util Util Util
Util Demand Demand Units
Final Final % Method %
Method
392360 392360 16384 20.00 1389.53 10^6bits/s 0.52 S 4.30
S 0.737 1.014 usec/KB
By the way, that double reporting of the local socket send size is fixed in:
------------------------------------------------------------------------
r516 | raj | 2012-01-05 15:48:52 -0800 (Thu, 05 Jan 2012) | 1 line
report the rsr_size_end in an omni stream test rather than a copy of the
lss_size_end
of netperf and later. Also, any idea why the local socket send size got
so much larger with 1GbE than 10 GbE at that setting of
tcp_limit_output_bytes?
Tests on Gbit link :
echo 16384 >/proc/sys/net/ipv4/tcp_limit_output_bytes
OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 172.30.42.18
(172.30.42.18) port 0 AF_INET
tcpi_rto 201000 tcpi_ato 0 tcpi_pmtu 1500 tcpi_rcv_ssthresh 14600
tcpi_rtt 1875 tcpi_rttvar 750 tcpi_snd_ssthresh 30 tpci_snd_cwnd 274
tcpi_reordering 3 tcpi_total_retrans 0
Local Local Local Elapsed Throughput Throughput Local Local
Remote Remote Local Remote Service
Send Socket Send Socket Send Time Units CPU CPU CPU
CPU Service Service Demand
Size Size Size (sec) Util Util Util
Util Demand Demand Units
Final Final % Method %
Method
1264784 1264784 16384 20.01 689.70 10^6bits/s 0.22 S
15.05 S 0.634 7.149 usec/KB
rick jones
_______________________________________________
Codel mailing list
[email protected]
https://lists.bufferbloat.net/listinfo/codel
