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Sdfits Online Tests

• Sdfits Online Tests
  • August 15 Tests
    • Tests:
    • Conclusion:
    • Action Item:
    • Gorry Details:

August 15 Tests

Tests:

I ran some tests of the offline Sdfits filler, making system calls from a python script just like the online filler. To cut to the chase, I found no smoking gun, no sig. difference between version of sdfits being ran, where it was being run, or even if the CPU was begin shared by an identical sdfits filler. This last variable was done to simulate the presence of the integration-level filler on sdfits.

Conclusion:

So, if there really has been a slow down of the online filler, it most likely has something to do with the dynamics of filling a scan that just ended: for instance the integration filler must sit in a wait loop while it waits for the last integration to finally get written to disk. This may have been slowing everything down.

It's interesting, and alarming to note that including the production of an index file increases run time by 50%. The good news is that that is a peformance factor I'm confident I can improve.

Action Item:

Run the same tests, but with real-time scans, and see if we can produce a slow-down.

Gorry Details:

command line: source /home/sparrow/5.5/sparrow.bash; python /home/sparrow/5.5/app/sdfits/sdfits.py /home/gbtdata/TREG_050814 -backends=acs -scans=115:116 -debug -index

Time     User       Version    Machine         Other
33.0     pmargani   5.3        nereid          No index (N/A for 5.3)
37.0     pmargani   5.4        nereid          No index
35.2     pmargani   5.5        nereid          No Index
51.2     pmargani   5.5        nereid
52.7     pmargani   5.4        nereid
55.0     pmargani   5.4        datacapture
49.5     pmargani   5.5        datacapture
46.0     monctrl    5.5        datacapture
47.0     monctrl    5.4        datacapture
53.0     monctrl    5.4        datacapture      2 processes
52.0     monctrl    5.5        datacapture      2 processes
43.0     monctrl    5.5        datacapture      2 processes to /home/sdfits
45.0     monctrl    5.4        datacapture      2 processes to /home/sdfits

-- PaulMarganian - 15 Aug 2005