1. 1 Testbeds Les Cottrell Site visit to SLAC by DoE program managers Thomas Ndousse & Mary Anne Scott April 27, 2005 www.slac.stanford.edu/grp/scs/net/talk05/testbeds-apr05.ppt Partially funded by DOE/MICS Field Work Proposal on Internet End-to-end Performance Monitoring (IEPM)

2. 2 CalTech/UMich lead, NSF funded project –Hybrid circuits (IP & dedicated)

3. 3 UltraScienceNet ORNL lead, DoE funded –Dedicated circuits

4. 4 UL Testbed 10Gbits/s Sunnyvale (interim until get ESnet 10Gbps circuits to SLAC, July 2005): –Currently UltraLIght –Cisco 6509 from UltraLight proposal –Four Sun v20z 1.8GHz Opterons loaned from BaBar –10GE TOE NICs loaned from Chelsio –4 10GE Neterion(S2io) 10GE NICs purchased Installed with Solaris-10 and Linux 2.6 –Will get file server from Caltech –Remote management Purchased/installed terminal server to provide console access Purchased/installed remote power management –Connect Cisco to 10Gbps UltraLight circuit –Interim USN IP connection imminent

5. 5 Sunnyvale set up Hosts have Solaris 1-, Linux 2.6, Neterio & Chelsio 10GE NICs.5.3.6 A3 A4 A5 A6 A2.8.7.4 Power Console 10Gbits/s UltraLight (192.84.86.x) CENIC http://137.164.37.3http://137.164.37.3 power management UltraLight 10Mbps management(134.164.37.x).18.19 Terminal Server Hub Compute servers

6. 6 Approaching 10Gbps performance Jumbo frames (1500Bytes std => 9000Bytes), factor of 6 improvement in recovery rate –Not an IEEE standard –May break some UDP applications –Not supported on many LANs Sender mods only, HENP model is few big senders, lots of smaller receivers –Simplifies deployment, only a few hosts at a few sending sites –So no Dynamic Right Sizing (DRS) at receiver XCP/ECN needs router mods so hard to deploy a new Internet

7. 7 Hardware Assists For 1Gbits/s paths, cpu, bus etc. not a problem For 10Gbits/s they are important NIC assistance to the CPU is becoming popular –Checksum offload –Interrupt coalescence –Large send/receive offload (LSO/LRO) –TCP Offload Engine (TOE) Several vendors for 10Gbits/s NICs, at least one for 1Gbits/s NIC But currently restricts to using NIC vendor’s TCP implementation Most focus is on the LAN –Cheap alternative to Infiniband, MyriNet etc.

8. 8 10Gbps test Sunfire vx0z, Linux & Solaris 10, Chelsio & Neterion Back-to-back (LAN) testing at SLAC SNV to LA At SC2004 using two 10Gbps dedicated paths between Pittsburgh and Sunnyvale –Using Solaris 10 (build 69) and Linux 2.6 –On Sunfire Vx0z (dual & quad 2.4GHz 64 bit AMD Opterons) with PCI-X 133MHz 64 bit –Only 1500 Byte MTUs Achievable performance limits (using iperf) –TOE (Chelsio) vs no TOE (Neterion(S2io)) –LSO vs no LSO support –Solaris 10 vs Linux UDTv2 evaluation

9. 9 CPU Utilization Receiver needs 20% less CPU than sender for high throughput For Neterion with LSO & Linux: Sender appears to use more CPU than receiver as the throughput increases Single stream limited by 1.8GHz CPU

10. 10 Effect of Jumbos Throughput SLAC-CENIC LA (1 stream, 2MB window with LSO Neterion(S2io)/Linux): –1500B MTU 1.8 Gbps –9000B MTU 6 Gbps Sender CPU: GHz/Gbps (single stream with LSO Neterion/Linux): –1500B MTU = 0.5 ± 0.13 GHz/Gbps –9000B MTU = 0.3 ± 0.07 GHz/Gbps –Factor 1.7 improvement For Neterion with LSO &Linux on WAN, Jumbos have a huge effect on performance and also improve CPU utilization

11. 11 Effect of LSO v20z 1.8GHz, Linux 2.6, S2io, 2 streams SLAC to Caltech, 8MB window: –With LSO: 7.4Gbits/s, –Without LSO: 5.4Gbits/s, LAN (3 streams, 164KB window) –Solaris => Linux: 6.4Gbps (No LSO support in Solaris 10 at the moment) –Linux => Solaris-10: 4.8Gbps (LSO turned off sender) –Linux => Solaris-10: 7.54Gbps (LSO turned on) For Neterion with Linux on LAN LSO improves CPU utilization by a factor of 1.4. If one is CPU limited this will also improve throughput. 1 stream

12. 12 Solaris vs Linux Send from one to the other single stream Compare send from Linux Neterion + LSO with send from Solaris 10 without LSO –LSO support for Solaris coming soon With one stream Solaris sender sends faster Sol slightly better GHz/Gbps GHz/Gbps: Solaris 0.287+-0.001; Linux 0.303+-0.001

13. 13 Solaris vs Linux multi- streams When optimize for multiple streams, Linux + LSO sender is better 1MB 2MB 4MB Solaris without LSO performs poorly with multiple streams (LSO or OS related?) –Its GHz/Gbps is poorer than Linux+LSO for multiple streams LAN MTU: 9400B S2io 7.5Gbps 6.4Gbps

14. 14 Chelsio Chelsio to Chelsio (TOE) With 2.4GHz V20zs from Pittsburgh to SNV 1500Byte MTUs Reliably able to get 7.4-7.5 Gbps (16 streams) GHz/Gbps Chelsio(MTU=1500B) ~ Neterion (9000B) Chelsio(TOE)

15. 15 SLAC Connection Part of ESnet Bay Area MAN –Will be 4 * 10GE circuits, 2 in 2 out for ring –QWest will connect to Stanford in next fortnight –Then cross-connect to SLAC/Stanford fibers and thus to SLAC Working with Stanford to ID fiber pairs

16. 16  Joint Caltech, SLAC, FNAL, CERN, UF, SDSC, BR, KR, ….  10 10 Gbps waves to HEP on show floor  Bandwidth challenge: aggregate throughput of 101.13 Gbps  FAST TCP SC2004: Tenth of a Terabit/s Challenge

17. 17 Bandwidth Challenge Large collaboration of academia and industry Took a lot of “wizards” to make it work >100 Gbps aggregate The prize!

18. 18 Conclusions UDT limit was ~ 4.45Gbits/s –Cpu limited TCP Limit was about 7.5±0.07 Gbps, regardless of: –Whether LAN (back to back) or WAN TCP Gating factor=PCI-X 133Mhz ≡ 7.5Gbps One host with 4 cpus & 2 NICs sent 11.5±0.2Gbps to two dual cpu hosts with 1 NIC each Two hosts to two hosts (1 NIC/host) on one 10Gbps link 9.07Gbps goodput forward & 5.6Gbps reverse

19. 19 Conclusions Jumbos can be a big help LSO is helpful (Neterion) For best throughput Linux+LSO sender better Without LSO Solaris provides more throughput Solaris without LSO has problems with multiple streams TOE (Chelsio) allows one to avoid 9000Byte MTUs

20. 20 Conclusions Need testing on real networks –Controlled simulation & emulation critical for understanding –BUT need to verify, and results can look different than expected Needs honest independent broker (SLAC) –Don’t care who wins, have the contacts, reputation, testbeds etc. –Not really funded for this

21. 21 Next Steps Evaluate various offloads (TOE, LSO, LRO...), Evaluate OS support: Solaris 10 support of LSO, untangle Solaris  Linux, Chelsio/TOE on Solaris, leverage industry contacts New buses: PCI-X 266Mhz and PCI-Express important, need NICs/hosts to support then evaluate Install IEPM-BW on 10Gbps testbed –Evaluate existing tools at 10Gbits/s –Explore new tools for 10Gbits/s Exploit relationships with Neterion/Chelsio to work with packet pair timing aided by NICs Install Passive tools (on 10Gbps testbeds and work with BNL to help achieve mission)) –Evaluate Netflow measurement & analysis at 10Gbits/s Privacy issues –Use SNMP to access MIBs utilization etc.

22. 22 Acknowledgements Gary Buhrmaster*, Parakram Khandpur*, Harvey Newman c, Yang Xia c, Xun Su c, Dan Nae c,Sylvain Ravot c, Richard Hughes-Jones m, Michael Chen +, Larry McIntosh s, Frank Leers s, Leonid Grossman n, Alex Aizman n SLAC*, Caltech c, Manchester University m, Chelsio +, Sun s, Neterion(S2io) n

23. 23 Further Information Web site with lots of plots & analysis –www.slac.stanford.edu/grp/scs/net/papers/pfld05/ruchig/Fairness/www.slac.stanford.edu/grp/scs/net/papers/pfld05/ruchig/Fairness/ Inter-protocols comparison (Journal of Grid Comp, PFLD04) –www.slac.stanford.edu/cgi-wrap/getdoc/slac-pub-10402.pdfwww.slac.stanford.edu/cgi-wrap/getdoc/slac-pub-10402.pdf SC2004 details –www-iepm.slac.stanford.edu/monitoring/bulk/sc2004/

24. 24 From LS Off MTU Byte s Median Thru GbpsIQR GHz/ GbpsIQR Linux On9400 7.395 0.015 0.416 0.015 Linux On1500 2.03 0.1 0.275 0.073 Linux Off9400 4.75 0.055 0.375 0.006 Solaris Off9400 6.2 0.02 0.287 0.001 Solaris Off1500 1.3 0.415 0.59 0.115

25. 25 When will it have an impact ESnet traffic doubling/year since 1990 SLAC capacity increasing by 90%/year since 1982 –SLAC Internet traffic increased by factor 2.5 in last year International throughput increase by factor 10 in 4 years So traffic increases by factor 10 in 3.5 to 4 years, so in: –3.5 to 5 years 622 Mbps => 10Gbps –3-4 years 155 Mbps => 1Gbps –3.5-5 years 45Mbps => 622Mbps 2010-2012: –100s Gbits for high speed production net end connections –10Gbps will be mundane for R&E and business –Home broadband: doubling ~ every year, 100Mbits/s by end of decade –Aggressive Goal: 1Gbps to all Californians by 2010 Throughput Mbits/s Throughput from US

26. 26 What was special? End-to-end application-to-application, single and multi- streams (not just internal backbone aggregate speeds) TCP has not run out of stream yet, scales from modem speeds into multi-Gbits/s region –TCP well understood, mature, many good features: reliability etc. –Friendly on shared networks New TCP stacks only need to be deployed at sender –Often just a few data sources, many destinations –No modifications to backbone routers etc –No need for jumbo frames Used Commercial Off The Shelf (COTS) hardware and software

27. 27 What was Special 2/2 Raise the bar on expectations for applications and users –Some applications can use Internet backbone speeds –Provide planning information The network is looking less like a bottleneck and more like a catalyst/enabler –Reduce need to colocate data and cpu –No longer ship literally truck or plane loads of data around the world –Worldwide collaborations of people working with large amounts of data become increasingly possible

28. 28 Who needs it? HENP – current driver –Multi-hundreds Mbits/s and Multi TByte files/day transferred across Atlantic today SLAC BaBar experiment already has a PByte stored –Tbits/s and ExaBytes (10 18 ) stored in a decade Data intensive science: –Astrophysics, Global weather, Bioinformatics, Fusion, seismology… Industries such as aerospace, medicine, security … Future: –Media distribution Gbits/s=2 full length DVD movies/minute 100 Gbits/s is equivalent to –Download Library of Congress in < 14 minutes –Three full length DVDs in a second Will sharing movies be like sharing music today?