Througput Performance between SLAC and Caltech

Les Cottrell. Page created: September 10, 3000.

Central Computer Access | Computer Networking | Network Group | ICFA-NTF Monitoring

Introduction

Caltech is a major BaBar collaborator (in particular it is one of 4 remote computing sites for BaBar and produces simulation data that is incorporated into the BaBar Objectivity database) and it important that there be high performance from Caltech to SLAC so data and results generated at Caltech can be quickly copied to SLAC. We received reports of poor performance (3Mbits/s) from Caltech to SLAC while SLAC to Caltech was seeing 25-30Mbits/s. These problems were first reported around August 15, 200 by Anders Ryd of Caltech and were assigned ESnet trouble ticket 6587. The issue was raised again by Jim Smith of Colorado on September 11, 2000.

PingER measurements

The packet loss (measured by PingER) appears to have been low (< 0.5%) for the 7 months (loss averaged over the month) prior to September 2000 and during September so far.

Routes

The route from SLAC to Caltech on September 10, 2000 appeared as follows:

traceroute to lugh.cacr.caltech.edu (131.215.145.183): 3-25 hops, 38 byte packets
 3  RTR-DMZ.SLAC.Stanford.EDU (134.79.111.4) [AS3671 - SU-SLAC]  1.85 ms (ttl=253)
 4  ESNET-A-GATEWAY.SLAC.Stanford.EDU (192.68.191.18) [AS32 - Stanford Linear Accelerator Center]  1.66 ms (ttl=252)
 5  gac2-atms.es.net (134.55.24.6) [AS293 - Energy Sciences Network (ESnet)]  18.0 ms (ttl=251)
 6  UCSD--esnet.ATM.calren2.net (198.32.248.69) [AS11422 - NET-C2-SOUTH]  18.3 ms (ttl=250)
 7  USC--UCSD.POS.calren2.net (198.32.248.33) [AS11422 - NET-C2-SOUTH]  22.5 ms (ttl=249)
 8  QAnh--USC.POS.calren2.net (198.32.248.17) [AS11422 - NET-C2-SOUTH]  22.2 ms (ttl=248)
 9  UCI--QAnh.POS.calren2.net (198.32.248.126) [AS11422 - NET-C2-SOUTH]  23.8 ms (ttl=247)
10  UCR--UCI.POS.calren2.net (198.32.248.13) [AS11422 - NET-C2-SOUTH]  24.5 ms (ttl=246)
11  CIT--UCR.POS.calren2.net (198.32.248.9) [AS11422 - NET-C2-SOUTH]  26.5 ms (ttl=245)
12  media-converter.caltech.edu (192.41.208.50) [AS31 - CIT-SSDP]  25.1 ms (ttl=244)
13  SFL-border.dmz.caltech.edu (192.12.19.252) [AS226 - California Institute of Technology]  26.2 ms (ttl=243)
14  CACR-rtr.ilan.caltech.edu (131.215.254.145) [AS226 - California Institute of Technology]  25.8 ms (ttl=242)
15  lugh.cacr.caltech.edu (131.215.145.183) [AS226 - California Institute of Technology]  25.3 ms (ttl=240!)

On September 11, 2000 the routing from SLAC to Caltech was changed to go via Stanford University andCalREN2 rather than via ESnet. the new route appears below:

traceroute to lugh.cacr.caltech.edu (131.215.145.183): 1-25 hops, 38 byte packets
 3  RTR-DMZ.SLAC.Stanford.EDU (134.79.111.4) [AS3671 - SU-SLAC]  1.53 ms (ttl=253)
 4  RTR-SUNET47.SLAC.Stanford.EDU (192.68.191.34) [AS32 - Stanford Linear Accelerator Center]  2.11 ms (ttl=252)
 5  Core-gateway.Stanford.EDU (171.64.1.115) [AS32 - BN-CIDR-171.64]  1.83 ms (ttl=251)
 6  i2-gateway.Stanford.EDU (171.64.1.209) [AS32 - BN-CIDR-171.64]  1.76 ms (ttl=250)
 7  STAN.POS.calren2.NET (171.64.1.213) [AS32 - BN-CIDR-171.64]  1.69 ms (ttl=249)
 8  SUNV--STAN.POS.calren2.net (198.32.249.73) [AS11423 - NET-C2-NORTH]  2.39 ms (ttl=248)
 9  abilene--QSV.POS.calren2.net (198.32.249.62) [AS11423 - NET-C2-NORTH]  7.62 ms (ttl=247)
10  losa-scrm.abilene.ucaid.edu (198.32.8.18) [AS226 - NETBLK-RA]  13.3 ms (ttl=246)
11  USC--abilene.ATM.calren2.net (198.32.248.85) [AS11422 - NET-C2-SOUTH]  52.6 ms (ttl=249!)
12  QAnh--USC.POS.calren2.net (198.32.248.17) [AS11422 - NET-C2-SOUTH]  58.2 ms (ttl=248!)
13  UCI--QAnh.POS.calren2.net (198.32.248.126) [AS11422 - NET-C2-SOUTH]  61.9 ms (ttl=247!)
14  UCR--UCI.POS.calren2.net (198.32.248.13) [AS11422 - NET-C2-SOUTH]  68.0 ms (ttl=246!)
15  CIT--UCR.POS.calren2.net (198.32.248.9) [AS11422 - NET-C2-SOUTH]  68.8 ms (ttl=245!)
16  media-converter.caltech.edu (192.41.208.50) [AS31 - CIT-SSDP]  74.0 ms (ttl=244!)
17  SFL-border.dmz.caltech.edu (192.12.19.252) [AS226 - California Institute of Technology]  69.7 ms (ttl=243!)
18  CACR-rtr.ilan.caltech.edu (131.215.254.145) [AS226 - California Institute of Technology]  60.7 ms (ttl=242!)
19  lugh.cacr.caltech.edu (131.215.145.183) [AS226 - California Institute of Technology]  62.4 ms (ttl=240!)

There appears to be no reverse traceroute server at Caltech, so Juan C. Barayoga [juan@hep.caltech.edu] rann a traceroute for me.

traceroute to WWWSLUG.SLAC.Stanford.EDU (134.79.18.131), 30 hops max, 38 byte packets

 1  Lauritsen-RSM-126.caltech.edu (131.215.126.253)  1.339 ms  0.617 ms  0.614 ms
 2  Booth-border.ilan.caltech.edu (131.215.254.254)  2.181 ms  0.948 ms  1.086 ms
 3  media.dmz.caltech.edu (192.12.19.249)  1.783 ms  0.975 ms  0.765 ms
 4  c2-gsr.caltech.edu (192.41.208.49)  2.820 ms  0.877 ms  1.084 ms
 5  UCR--CIT.POS.calren2.net (198.32.248.10)  2.345 ms  2.419 ms  2.623 ms
 6  UCI--UCR.POS.calren2.net (198.32.248.14)  4.736 ms  3.803 ms  3.539 ms
 7  QAnh--UCI.POS.calren2.net (198.32.248.125)  4.156 ms  4.997 ms  4.325 ms
 8  USC--QAnh.POS.calren2.net (198.32.248.18)  4.206 ms  3.985 ms  4.009 ms
 9  UCSD--USC.POS.calren2.net (198.32.248.34)  8.531 ms  8.230 ms  7.779 ms
10  esnet--UCSD.ATM.calren2.net (198.32.248.70)  45.771 ms  7.938 ms  8.790 ms
11  slac1-atms.es.net (134.55.24.13)  26.194 ms  26.757 ms  25.554 ms
12  * * *
13  * * *
14  * * *
15  WWWSLUG.SLAC.Stanford.EDU (134.79.18.131)  21.827 ms  25.976 ms  22.115 ms

Pingroute

Pingroute from SLAC to lugh.cacr.caltech.edu on September 10, is shown below. When this measurement was made there appears to have been little (< 1%) loss for either small (100byte) or large (1400 byte) packets.

2cottrell@pharlap:~>pingroute.pl -c 100 lugh.cacr.caltech.edu
Sun Sep 10 14:59:30 2000
 Architecture=SUN5, commands=traceroute -q 1 and ping -s node 1400 100, pingroute.pl version=1.4, 5/16/00, debug=1
pingroute.pl version 1.4, 5/16/00 using traceroute to get nodes in route from pharlap to lugh.cacr.caltech.edu
traceroute: Warning: ckecksums disabled
traceroute: Warning: Multiple interfaces found; using 134.79.16.102 @ qfe1
traceroute to lugh.cacr.caltech.edu (131.215.145.183), 30 hops max, 40 byte packets
pingroute.pl version 1.4, 5/16/00 found 15 hops in route from pharlap to lugh.cacr.caltech.edu
4  ESNET-A-GATEWAY.SLAC.Stanford.EDU (192.68.191.18)  0.938 ms
5  gac2-atms.es.net (134.55.24.6)  48.453 ms
6  UCSD--esnet.ATM.calren2.net (198.32.248.69)  34.704 ms
7  USC--UCSD.POS.calren2.net (198.32.248.33)  54.358 ms
8  QAnh--USC.POS.calren2.net (198.32.248.17)  54.803 ms
9  UCI--QAnh.POS.calren2.net (198.32.248.126)  52.124 ms
10  UCR--UCI.POS.calren2.net (198.32.248.13)  57.540 ms
11  CIT--UCR.POS.calren2.net (198.32.248.9)  65.949 ms
12  media-converter.caltech.edu (192.41.208.50)  59.489 ms
13  SFL-border.dmz.caltech.edu (192.12.19.252)  69.309 ms
14  CACR-rtr.ilan.caltech.edu (131.215.254.145)  62.714 ms
15  lugh.cacr.caltech.edu (131.215.145.183)  69.011 ms
Wrote 15 addresses to /tmp/pingaddr, now ping each address 100 times from pharlap
         pings/node=100                              100 byte packets           1400 byte packets
         NODE                                  %loss    min    max    avg %loss   min    max    avg from pharlap
192.68.191.18   ESNET-A-GATEWAY.SLAC.STANFORD.    0%    0.0  194.0    6.0   0%    2.0  162.0    7.0 Sun Sep 10 15:09:25 PDT 2000
134.55.24.6     GAC2-ATMS.ES.NET                  0%   17.0  178.0   23.0   0%   19.0  276.0   35.0 Sun Sep 10 15:12:43 PDT 2000
198.32.248.69   UCSD--ESNET.ATM.CALREN2.NET       0%   18.0   20.0   18.0   0%   20.0   22.0   20.0 Sun Sep 10 15:16:02 PDT 2000
198.32.248.33   USC--UCSD.POS.CALREN2.NET         0%   18.0   21.0   18.0   0%   20.0   23.0   20.0 Sun Sep 10 15:19:20 PDT 2000
198.32.248.17   QANH--USC.POS.CALREN2.NET         0%   18.0   22.0   18.0   0%   21.0   24.0   21.0 Sun Sep 10 15:22:38 PDT 2000
198.32.248.126  UCI--QANH.POS.CALREN2.NET         0%   19.0   22.0   19.0   0%   22.0   24.0   22.0 Sun Sep 10 15:25:56 PDT 2000
198.32.248.13   UCR--UCI.POS.CALREN2.NET          0%   20.0   22.0   20.0   0%   23.0   25.0   23.0 Sun Sep 10 15:29:15 PDT 2000
198.32.248.9    CIT--UCR.POS.CALREN2.NET          0%   21.0   23.0   21.0   0%   24.0   26.0   24.0 Sun Sep 10 15:32:33 PDT 2000
192.41.208.50   MEDIA-CONVERTER.CALTECH.EDU       0%   24.0   25.0   24.0   0%   27.0   28.0   27.0 Sun Sep 10 15:35:51 PDT 2000
192.12.19.252   SFL-BORDER.DMZ.CALTECH.EDU        0%   26.0  104.0   27.0   0%   29.0  243.0   34.0 Sun Sep 10 15:39:09 PDT 2000
131.215.254.145 CACR-RTR.ILAN.CALTECH.EDU         0%   26.0   49.0   26.0   0%   29.0   33.0   30.0 Sun Sep 10 15:42:27 PDT 2000
131.215.145.183 LUGH.CACR.CALTECH.EDU             0%   26.0   28.0   26.0   0%   30.0   33.0   30.0 Sun Sep 10 15:45:45 PDT 2000

The pingroute measurement from SLAC to Caltech after the route was changed to send traffic from SLAC to Caltech via the Stanford campus and CalREN2 rather than by ESnet.

9cottrell@flora01:~>bin/pingroute.pl -c 100 lugh.cacr.caltech.edu
Mon Sep 11 11:07:26 2000
 Architecture=SUN5, commands=traceroute -q 1 and ping -s node 1400 100, pingroute.pl version=1.4, 5/16/00, debug=1
pingroute.pl version 1.4, 5/16/00 using traceroute to get nodes in route from flora01 to lugh.cacr.caltech.edu
traceroute: Warning: ckecksums disabled
traceroute to lugh.cacr.caltech.edu (131.215.145.183), 30 hops max, 40 byte packets
pingroute.pl version 1.4, 5/16/00 found 19 hops in route from flora01 to lugh.cacr.caltech.edu
4  RTR-SUNET47.SLAC.Stanford.EDU (192.68.191.34)  2.742 ms
5  Core-gateway.Stanford.EDU (171.64.1.115)  1.276 ms
6  i2-gateway.Stanford.EDU (171.64.1.209)  1.916 ms
7  STAN.POS.calren2.NET (171.64.1.213)  2.133 ms
8  SUNV--STAN.POS.calren2.net (198.32.249.73)  2.438 ms
9  abilene--QSV.POS.calren2.net (198.32.249.62)  7.411 ms
10  losa-scrm.abilene.ucaid.edu (198.32.8.18)  12.620 ms
11  USC--abilene.ATM.calren2.net (198.32.248.85)  66.815 ms
12  ISI--USC.POS.calren2.net (198.32.248.26)  74.395 ms
13  UCLA--ISI.POS.calren2.net (198.32.248.30)  73.344 ms
14  JPL--UCLA.POS.calren2.net (198.32.248.2)  69.756 ms
15  CIT--JPL.POS.calren2.net (198.32.248.6)  72.575 ms
16  media-converter.caltech.edu (192.41.208.50)  75.949 ms
17  Booth-border.dmz.caltech.edu (192.12.19.254)  38.460 ms
18  CACR-rtr.ilan.caltech.edu (131.215.254.145)  26.945 ms
19  lugh.cacr.caltech.edu (131.215.145.183)  47.004 ms
Wrote 19 addresses to /tmp/pingaddr, now ping each address 100 times from flora01
         pings/node=100                              100 byte packets           1400 byte packets
         NODE                                  %loss    min    max    avg %loss   min    max    avg from flora01
192.68.191.34   RTR-SUNET47.SLAC.STANFORD.EDU     0%    1.0   32.0    2.0   0%    3.0  116.0    5.0 Mon Sep 11 11:17:26 PDT 2000
171.64.1.115    CORE-GATEWAY.STANFORD.EDU         0%    1.0    5.0    1.0   0%    3.0   10.0    3.0 Mon Sep 11 11:20:44 PDT 2000
171.64.1.209    I2-GATEWAY.STANFORD.EDU           0%    1.0   18.0    2.0   0%    3.0    6.0    3.0 Mon Sep 11 11:24:03 PDT 2000
171.64.1.213    STAN.POS.CALREN2.NET              0%    1.0    4.0    1.0   0%    3.0   20.0    3.0 Mon Sep 11 11:27:21 PDT 2000
198.32.249.73   SUNV--STAN.POS.CALREN2.NET        0%    3.0    8.0    3.0   0%    5.0   18.0    5.0 Mon Sep 11 11:30:39 PDT 2000
198.32.249.62   ABILENE--QSV.POS.CALREN2.NET      0%    6.0   13.0    6.0   0%    8.0   21.0    9.0 Mon Sep 11 11:33:57 PDT 2000
198.32.8.18     LOSA-SCRM.ABILENE.UCAID.EDU       0%   11.0   23.0   12.0   0%   14.0   20.0   14.0 Mon Sep 11 11:37:15 PDT 2000
198.32.248.85   USC--ABILENE.ATM.CALREN2.NET      0%   16.0   19.0   16.0   0%   18.0   25.0   19.0 Mon Sep 11 11:40:33 PDT 2000
198.32.248.26   ISI--USC.POS.CALREN2.NET          0%   16.0   19.0   17.0   0%   19.0   21.0   19.0 Mon Sep 11 11:43:51 PDT 2000
198.32.248.30   UCLA--ISI.POS.CALREN2.NET         0%   17.0   24.0   17.0   0%   20.0   22.0   20.0 Mon Sep 11 11:47:10 PDT 2000
198.32.248.2    JPL--UCLA.POS.CALREN2.NET         0%   17.0   21.0   18.0   0%   20.0   27.0   21.0 Mon Sep 11 11:50:28 PDT 2000
198.32.248.6    CIT--JPL.POS.CALREN2.NET          0%   19.0   32.0   19.0   0%   22.0   24.0   22.0 Mon Sep 11 11:53:46 PDT 2000
192.41.208.50   MEDIA-CONVERTER.CALTECH.EDU       0%   21.0   23.0   21.0   0%   23.0   31.0   24.0 Mon Sep 11 11:57:05 PDT 2000
192.12.19.254   BOOTH-BORDER.DMZ.CALTECH.EDU      0%   18.0   82.0   20.0   0%   22.0  170.0   24.0 Mon Sep 11 12:00:23 PDT 2000
131.215.254.145 CACR-RTR.ILAN.CALTECH.EDU         1%   20.0   22.0   20.0   0%   24.0   58.0   24.0 Mon Sep 11 12:03:42 PDT 2000
131.215.145.183 LUGH.CACR.CALTECH.EDU             0%   20.0   91.0   22.0   0%   24.0   61.0   24.0 Mon Sep 11 12:07:01 PDT 2000

Path characterization

We used pathchar to characterize the route. The results are shown below. When this measurment was made the bottlneck appears to have been between SLAC and the ESnet ATM network (28Mbits/s). The localhost at SLAC was a reasonably loaded general purpose machine with a 100Mbps Ethernet interface. It was not one of the machines used for production or test thruput performance. The reason for this is due to not having root access to run pathchar on the thruput machines.

pathchar to lugh.cacr.caltech.edu (131.215.145.183)
 mtu limitted to 1500 bytes at FLORA01.SLAC.Stanford.EDU (134.79.16.29)
 doing 32 probes at each of 64 to 1500 by 44
 0 localhost
 |    25 Mb/s,   210 us (0.91 ms)
 1 router1.SLAC.Stanford.EDU 
 |    77 Mb/s,   166 us (1.39 ms)
 2 router2.SLAC.Stanford.EDU
 |   118 Mb/s,   57 us (1.61 ms)
 3 router3.SLAC.Stanford.EDU 
 |   114 Mb/s,   -107 us (1.50 ms)
 4 ESNET-A-GATEWAY.SLAC.Stanford.EDU (192.68.191.18)
 |    28 Mb/s,   8.16 ms (18.3 ms)
 5 gac2-atms.es.net (134.55.24.6)
 |    36 Mb/s,   59 us (18.7 ms)
 6 UCSD--esnet.ATM.calren2.net (198.32.248.69)
 |   337 Mb/s,   1.76 ms (22.3 ms)
 7 USC--UCSD.POS.calren2.net (198.32.248.33)
 |   321 Mb/s,   268 us (22.8 ms)
 8 ISI--USC.POS.calren2.net (198.32.248.26)
                        -> 198.32.248.26 (1)           
 |   336 Mb/s,   240 us (23.3 ms)
 9?UCLA--ISI.POS.calren2.net (198.32.248.30)
 |   112 Mb/s,   285 us (24.0 ms)
10 JPL--UCLA.POS.calren2.net (198.32.248.2)
 |   354 Mb/s,   759 us (25.6 ms)
11 CIT--JPL.POS.calren2.net (198.32.248.6)
 |   284 Mb/s,   -2 us (25.6 ms)
12 media-converter.caltech.edu (192.41.208.50)
 |    48 Mb/s,   -267 us (25.3 ms)
13 Booth-border.dmz.caltech.edu (192.12.19.254)
 |    65 Mb/s,   613 us (26.7 ms)
14 CACR-rtr.ilan.caltech.edu (131.215.254.145)
15  * 1   504 528      32       ->131.215.254.145 (1)

The pathchar after the routing was changed to go via CalREN2 appears below (measured 9/20/00):

pathchar to lugh.cacr.caltech.edu (131.215.145.183)
 mtu limitted to 1500 bytes at FLORA05.SLAC.Stanford.EDU (134.79.16.59)
 doing 32 probes at each of 64 to 1500 by 44
 0 FLORA05.SLAC.Stanford.EDU (134.79.16.59)
 |    25 Mb/s,   213 us (0.91 ms)
 1 RTR-CORE1.SLAC.Stanford.EDU (134.79.19.2)
 |    83 Mb/s,   187 us (1.42 ms)
 2 RTR-CGB6.SLAC.Stanford.EDU (134.79.135.6)
 |   110 Mb/s,   73 us (1.68 ms)
 3 RTR-DMZ.SLAC.Stanford.EDU (134.79.111.4)
                        -> 134.79.111.4 (3)           
 |    53 Mb/s,   102 us (2.11 ms)
 4?RTR-SUNET47.SLAC.Stanford.EDU (192.68.191.34)
 |   167 Mb/s,   -58 us (2.07 ms)
 5 Core-gateway.Stanford.EDU (171.64.1.115)
 |   171 Mb/s,   -1 us (2.13 ms)
 6 i2-gateway.Stanford.EDU (171.64.1.209)
 |   219 Mb/s,   28 us (2.25 ms)
 7 STAN.POS.calren2.NET (171.64.1.213)
 |   101 Mb/s,   145 us (2.65 ms)
 8 SUNV--STAN.POS.calren2.net (198.32.249.73)
 |   ?? b/s,   1.63 ms (5.84 ms)
 9 abilene--QSV.POS.calren2.net (198.32.249.62)
 |    71 Mb/s,   3.50 ms (13.0 ms)
10 losa-scrm.abilene.ucaid.edu (198.32.8.18)
 |   ?? b/s,   122 us (13.2 ms)
11 USC--abilene.ATM.calren2.net (198.32.248.85)
 |   282 Mb/s,   427 us (14.1 ms)
12 QAnh--USC.POS.calren2.net (198.32.248.17)
 |   103 Mb/s,   309 us (14.8 ms)
13 UCI--QAnh.POS.calren2.net (198.32.248.126)
 |   ?? b/s,   654 us (16.1 ms)
14 UCR--UCI.POS.calren2.net (198.32.248.13)
 |   109 Mb/s,   787 us (17.8 ms)
15 CIT--UCR.POS.calren2.net (198.32.248.9)
 |   275 Mb/s,   -633 us (16.6 ms)
16 media-converter.caltech.edu (192.41.208.50)
 |    48 Mb/s,   370 us (17.6 ms)
17 SFL-border.dmz.caltech.edu (192.12.19.252)
 |    82 Mb/s,   -48 us (17.6 ms)
18 CACR-rtr.ilan.caltech.edu (131.215.254.145)
19  * 1   812 527      17
^C:  13   328 323      17

Iperf TCP thruput

Measurements using iperf were also made. It appears that from SLAC to Caltech using the ESnet path one could get > 25Mbps throughput with the approriate number of streams and windows (see Bulk Thruput measurements). Below is shown the iperf TCP thruput for September 10, 2000. The backgroun load (as seen in SLAC ATM to ESnet) was about 6Mbits/ outbound from SLAC and 9 Mbits/s inbound to SLAC. The maximum inbound and outbound loads appear to peak at about 35Mbps, so the above background loads are light. As far as I am aware there are no similar utilization plots for the Caltech external lines. CalREN2 keeps Router/Switch Interface Statistics which provide information on the Caltech to CalREN2 link utilization and on the CalREN2 ro ESnet gateway utilization. An iperf server was installed at SLAC to enable someone with an account on a machine at Caltech to check the reverse path. Below is the iperf throughput from Caltech to SLAC; the performance is almost a factor of 20 worse than from SLAC to Caltech. We got similar results from SDSC to SLAC. From the traceroute above it appears that SDSC is on the route from Caltech to SLAC and is close to where Calren2 traffic crosses over to ESnet.

lugh% ./iperf -c pharlap.slac.stanford.edu -p 5007 -w 256k -P 6
------------------------------------------------------------
Client connecting to pharlap.slac.stanford.edu, TCP port 5007
TCP window size:  256 KByte
------------------------------------------------------------
[  9] local 131.215.145.183 port 38117 connected with 134.79.16.102 port 5007
[  6] local 131.215.145.183 port 38114 connected with 134.79.16.102 port 5007
[  5] local 131.215.145.183 port 38112 connected with 134.79.16.102 port 5007
[  4] local 131.215.145.183 port 38113 connected with 134.79.16.102 port 5007
[  7] local 131.215.145.183 port 38115 connected with 134.79.16.102 port 5007
[  8] local 131.215.145.183 port 38116 connected with 134.79.16.102 port 5007
[ ID] Interval       Transfer     Bandwidth
[  9]  0.0-11.1 sec   776 KBytes   561 Kbits/sec
[  6]  0.0-11.2 sec   776 KBytes   556 Kbits/sec
[  5]  0.0-11.3 sec   520 KBytes   367 Kbits/sec
[  7]  0.0-12.1 sec   1.0 MBytes   682 Kbits/sec
[  4]  0.0-12.3 sec   1.3 MBytes   846 Kbits/sec
[  8]  0.0-13.1 sec   264 KBytes   161 Kbits/sec

On September 11, 2000 SLAC and Stanford changed the routing from SLAC to Caltech to use Stanford/CalREN2 rather than ESnet. The new route is given above. With the new route the performance was about doubled. See below:

Sometime between 9/14/00 and 9/18/00 the routing of packets from UCSD to SLAC was changed to go via CalREN2 rather than via ESnet. We were unable to provide a traceroute from lugh since we could not find traceroute on lugh. Following the route change we used iperf with a 256kByte window and got 19Mbits/s with 1 stream and 25Mbps with 10 streams from lugh.cacr.caltech.edu and pharlap.slac.stanford.edu. This is still below the 50Mbits/s fmeasured from SLAC to Caltech. We requested the isntallation of pathchar on lugh to assist in finding nthe bottleneck from Caltech to SLAC.

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Page owner: Les Cottrell