Download presentation
Presentation is loading. Please wait.
1
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 1 EU DataGrid - Network Monitoring Richard Hughes-Jones, University of Manchester Thanks to a wireless connected Titanium in the garden@Houten
2
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 2 European Topology: NRNs & Geant SuperJANET4 CERN UvA Manc SURFnet
3
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 3 Gigabit Throughput on the Production WAN Manc - RAL 570 Mbit/s 91% of the 622 Mbit access link between SuperJANET4 and RAL 1472 bytes propagation ~21 s Manc-UvA (SARA) 750 Mbit/s SJANET4 + Geant + SURFnet Manc – CERN 460 Mbit/s CERN PC had a 32 bit PCI bus
4
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 4 Gigabit TCP on the Production WAN (01) Throughput vs TCP buffer size TCP window sizes in Mbytes calculated from RTT*bandwidth Window for BW 1 Gbit/s Window Mbytes for UDP BW 750 Mbit/s 460 Mbit/s
5
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 5 Gigabit TCP on the Production WAN Man-CERN Throughput vs n-streams Default buffer size slope = ~25 Mbit/s/stream up to 9 streams then 15 Mbit/s/stream With larger buffers rate of increase per stream is larger Plateaus at about 7 streams giving a total throughput of ~400 Mbit/s
6
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 6 UDP Throughput: SLAC - Man SLAC – Manc 470 Mbit/s 75% of the 622 Mbit access link SuperJANET4 peers with ESnet at 622Mbit in NY
7
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 7 Gigabit TCP on throughput Man-SLAC Throughput vs n-streams Much less than for European links Buffer required: rtt*BW (622Mbit) = ~14 Mbytes With larger buffers > default, rate of increase per stream is ~ 5.4 Mbit/s/stream No Plateau
8
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 8 RiPE 1 way UvA RAL ms RiPE 1 way RAL UvA ms UDPmon Loss Throughput Mbit/s MAN – UvA ~750Mbit/s UDPmon & Ripe MAN-SARA from 25 May 02
9
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 9 UDPmon Loss Throughput ~140 Mbit/s Man Lyon Ping Man Lyon 40 ms rtt Iperf TCP Throughput ~ 47 Mbit/s Man Lyon 1048576 byte buffer iperf Pinger & UDPmon UK-Lyon From 25 May 02 – 04 Jun 02
10
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 10 Work on End Systems: PCI: SysKonnect SK-9843 Motherboard: SuperMicro 370DLE Chipset: ServerWorks III LE Chipset CPU: PIII 800 MHz PCI:64 bit 66 MHz RedHat 7.1 Kernel 2.4.14 SK301 1400 bytes sent Wait 20 us Sk303 1400 bytes sent Wait 10 us Frames are back-to-back Can drive at line speed Cannot go any faster ! Gig Eth frames back to back
11
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 11 PCI: Intel Pro/1000 Motherboard: SuperMicro 370DLE Chipset:: ServerWorks III LE Chipset CPU: PIII 800 MHz PCI:64 bit 66 MHz RedHat 7.1 Kernel 2.4.14 IT66M212 1400 bytes sent Wait 11 us ~4.7us on send PCI bus PCI bus ~45% occupancy ~ 3.25 us on PCI for data recv IT66M212 1400 bytes sent Wait 11 us Packets lost Action of pause packet?
12
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 12 UDP Throughput: Intel Pro/1000 on B2B P4DP6 Max throughput 950Mbit/s Some throughput drop for packets >1000 bytes Loss NIC dependent Loss not due to user Kernel moves Traced to discards in the receiving IP layer ??? Motherboard: SuperMicro P4DP6 Chipset: Intel E7500 (Plumas) CPU: Dual Xeon Prestonia (2cpu/die) 2.2 GHz Slot 4: PCI, 64 bit, 66 MHz RedHat 7.2 Kernel 2.4.14
13
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 13 Packet Loss: Where? Intel Pro 1000 on 370DLE 1472 byte packets Expected loss in transmitter ! UDPmon UDP IP Eth drv UDPmon UDP IP Eth drv HW N Gen N Transmit N Lost IpDiscards N Received Gig Switch No loss at switch But Pause packet seen to sender
14
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 14 Interrupt Coalescence: Latency Intel Pro 1000 on 370DLE 800 MHz CPU
15
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 15 Interrupt Coalescence: Latency Intel Pro 1000 on 370DLE 800 MHz CPU
16
CdL was here DataTAG/WP7 Amsterdam June 2002 R. Hughes-Jones Manchester 16 Interrupt Coalescence: Throughput Intel Pro 1000 on 370DLE
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.