Flexbuf - MIT Haystack Observatory

More documents

Recommendations

Info

Utilities ◮ Service (aka. Daemon) scripts: Ready after boot. ◮ Recpoint formatting/tuning/mounting script. ◮ Hugepage initialization ◮ Parsing of logs to gnuplottable format ◮ Plotting of parsed logs. (Daily integration tests for regression testing etc.) ◮ Queueing scripts. ◮ vbs_record nameoftest 300 -s 47338 -q vdif ◮ Extraction of schedule from snp-file. ◮ vbs_delete, vbs_ls.. <strong>Flexbuf</strong> October 23, 2012 22/24
Development and faults ◮ Delayed sending (eg. send packet every 35 ms) is currently done in busyloop ◮ Regular kernel min. sleep times tend to be ~50ms. ◮ Multiple sending threads clog system with busy loops. ◮ TCP congestion control etc. actually handle this automatically. ◮ Needs QoS Solution 1. An interrupt facility with function pointers. ◮ Accuracy to be tested. Solution 2. Kernel socket option for rate control Solution 3. Kernel Pre-emption and nanosleep (Thanks Paul) ◮ Set sender threads to higher priorities ◮ Kernel pre-emption needs to be set => Kernel tuning ◮ ./configure –enable-nanosleep=yes <strong>Flexbuf</strong> October 23, 2012 23/24
Page 1 and 2: Flexbuf Tomi Salminen, Ari Mujunen
Page 3 and 4: Hardware Flexbuf October 23, 2012 3
Page 5 and 6: Hardware on Watt Motherboard Superm
Page 7 and 8: Challenges ◮ Ye olde spinning har
Page 9 and 10: ◮ Special socket options like rxr
Page 11 and 12: ◮ Uses a schedule (eg. VLBI sessi
Page 13 and 14: Uses ◮ Main design purpose is sta
Page 15 and 16: Flexbuf October 23, 2012 15/24
Page 17 and 18: Percentage 600 500 400 300 200 100
Page 19 and 20: Flexbuf October 23, 2012 19/24
Page 21: Flexbuf October 23, 2012 21/24

Flexbuf - MIT Haystack Observatory

Create successful ePaper yourself

Delete template?

Save as template?