On-demand file transfer for ITER remote experiments

Transcription

1 The 11 th IAEA-TM on Control, Data Acquisition, and Remote Participation for Fusion Research May 8-12, 2017, Greifswald, Germany On-demand file transfer for ITER remote experiments K.YAMANAKA 1, H.NAKANISHI 2, T.OZEKI 3, N.NAKAJIMA 2, S.ABE 1, S.URUSHIDANI 1, T.YAMAMOTO 2, H.ISHI 3 1 National Institute of Informatics (NII), Japan 2 National Institute of Fusion Science (NIFS), Japan 3 National Institutes for Quantum and Radiological Science and Technology (QST), Japan

2 Outline 1. ITER Remote Experiment Center (REC) 2. ITER-REC data transfer experiment and results 3. Next step for fast data transfer between ITER and REC 4. SINET update and next MMCFTP s experiment 5. Conclusion 1

3 ITER Remote Experimentation Centre (REC) The ITER remote experimentation centre will be made to participate the experiment remotely, where the experimental proposal and data collection and analyses will be done through the broad band network. Goal: making local and remote sites equivalent regarding data accessibility. 2

4 ITER Data Estimate ITER phase Total DAN archive rate Plasma duration Time Data volume per shot Initial 2 GB/s (16 Gbps) s ( min) 800 GB - 1 TB Final 50 GB/s (400 Gbps) 1000 s (16.7 min) 50 TB DAN: Data Archive Network Data per shot to be sent to REC Data to be sent to REC: - Minimum: Shot data measured by remote experiments - Maximum: Shot data measured by ITER experiments Data transfers of shot by shot are required 3

5 2. ITER-REC data transfer experiment and results 4

6 ITER REC Test Conditions Demonstrate the long data transfer (ITER REC) of 8h, 16h, 50h with: ITER data (initial): 2GB x 500s 1 TB/pulse Target speed 8 Gbps through 10 Gbps link 20 pulse/day 30 min. cyclic 1 TB transfer takes 1000 sec (approx. 17 min) in ideal condition. Real fusion diagnostics data of LHD and JT-60U were used. 8h, 16h, and 50h are supposed to daily, 2 work shift, and 3 shift 2 days ope. Data were transferred by MMCFTP protocol. ITER (Cadarache, France) ii. Plasma Operation Fast storage i. Preset parameters Test Scope Int l Research Network Fast storage REC (Rokkasho, Japan) iii. Whole data transfer Main storage Long-term data archive v. Reflect results for the next discharge Replicated storage iv. Data analyses 5

7 MMCFTP (Massively Multi-Connection FTP) MMCFTP is a new file transfer protocol designed for international sharing of big data. MMCFTP uses several thousands of TCP connections to sustain the specified target speed, and controls the number of TCP connections dynamically according to network conditions. MMCFTP achieved 150 Gbps data transfer speed between Tokyo and Salt Lake City at SC16. A world record of long distance data transfer 6

8 Test Results (whole week) Typhoon attack Link lost 30 th 13:10 31 st 09:50 CEST (30 th 20:10 31 st 16:50 JST) 2 nd PR video taken Tests were made with NIFS. 8-hour Test 16-hour Test 50-hour Test 1 st PR video taken Traffic monitored here! 7

9 RENATER Traffics in Tests in 16-hour test % of 10G line, % of 20G line were used. 8

10 50-hour Test Results 1.05 TB data were transferred 100 times repeatedly during 50 hours. 50 TB/day (100 TB in 2 days) This established a new record of inter-continental long data transfer between single point-to-point connection. Effective transfer rate and time - max.: Gbps, Elapsed time: 17 min 46 sec - min.: Gbps, Elapsed time: 25 min 43 sec Completed within 30 min. cycle - Ave.: Gbps, Elapsed time: 19 min 42 sec 7.9 Gbps (max.) 5.5 Gbps (min.) 9

11 Conclusion of data transfer tests in ITER-REC Prospect is obtained that researchers can remotely participate in ITER exp. via REC in an equivalent environment to the ITER in situ. Problem of Transfer rate slower for longer distances can be solved by using adequate data transfer schemes. To make REC a mirror site of the whole measured data of ITER exp. might be possible. ITER Newsline GÉANT CONNET Issue 24 10

12 3. Next step for fast data transfer between ITER and REC 11

13 A next task for ITER-REC data transfer In the ITER-REC data transfer test, we used a 1TB tar-archived file that includes many data files acquired by LHD and JT-60U. In the real ITER-REC data transfer, we should deal with many files directly. To reduce delay of data accessibility for REC users, data file should divide by an appropriate time slice. Because such a file division enables applying pipeline technique to ITER-REC data transfers. Without Pipeline A plasma shot Data writing to files File processing Transferring to REC File processing With Pipeline Delay for REC users Time slice Delay for REC users 12

14 Pipeline technique and MMCFTP MMCFTP has a few seconds overhead in a file transfer session. Such a overhead is not problem if a time slice is long, such as 1 min. A shorter time slice, such as 10s, is better to reduce latency for REC users. To support a short time slice, MMCFTP should reduce overhead. MMCFTP: Protocol overview User Sender appl. Receiver daemon Start a sender appl. Start a receiver daemon Main source of MMCFTP s overhead Several thousands of TCP connections are established loop Several thousands of TCP connections are closed 13

15 An extension for MMCFTP If a series of file transfers share established TCP connections, MMCFTP can reduce overhead. Such an extension will be also useful to send many files. MMCFTP s sender appl. MMCFTP s receiver daemon MMCFTP s sender daemon Queue TCP connections are established for each file transfer MMCFTP s receiver daemon TCP connections are kept in a series of file transfers 14

16 4. SINET update and next MMCFTP s experiment 15

17 SINET Update EU-Japan lines have used by many advance research projects, and traffic growth is more remarkable than expected. NII has a plan to upgrade the EU-Japan line from two 10 G lines to a 100 G line at FY The landing point may change to Amsterdam. SURFnet NORDUnet These two lines will be upgraded at FY CAnet4 London Amsterdam GÉANT TEIN Tokyo CalREN Pacific Wave Los Angeles ESnet Internet2 MAN LAN New York Singapore RedCLARA AARnet REUNA Traffic status on a EU-Japan line Aug Jan

18 Next MMCFTP s Experiment at TNC 17 SINET5 10Gx2 Target speed: 150 Gbps (Memory to Memory) 100 Gbps (Disk to Disk) SINET5 10Gx2 Tokyo TransPAC/PacificWave 100G SINET5 100G 150 Gbps at SC16 (Memory to Memory) Seattle LAX Internet2 NEAAR 100G London NYC Géant 100G (ANA-300) Paris TNC17 Linz, Austria 17

19 Conclusion The ITER-REC data transfer test and results were presented. The results have successfully demonstrated the possibility to build a full replication site of ITER data even at a distance. An extension of MMCFTP was presented to reduce overheads for short-term file transfers. 18

20 Thank you very much! 19

21 Appendix: Specification of PCs at TNC 17 M.2 x 4 M.2 x 2 20