Ryan S, Jason, Dave:

In the past few days cds_report was flagging a large log file for h1daqnds1. On investigation I found it was due to the DIAG_MAIN guardian node asking for 10 second trends of H1:PSL-ISS_DIFFRACTION_AVG eight times every second. This was generating +630k logs daily over the past few days.

Working with Ryan S, the problem was found to be due to the ISS diffraction avg signal trending downwards and going below DIAG_MAIN's  2.5 low limit, which was then requesting the 10 second averages of this channel from the DAQ.

In consultation with Jason, Ryan made two changes:

1. Boosted the ISS diffraction avg back up above 2.5 [see attached trend]

2. Removed the code which requests the 10 second average of the average channel, the 1 second average this channel represents is sufficient lookback [DIAG_MAIN.py code change shown below]

  665 @SYSDIAG.register_test
 666 def PSL_ISS():
 667     """ISS diffracted power
 668 
 669     """
 670     diff_high = 5.5
 671     diff_low = 2.5
 672     if PSL_on():
 673     ¦   diff_now = ezca['PSL-ISS_DIFFRACTION_AVG']
 674     ¦   # if diff_now > diff_high:
 675     ¦   #     diff_pwr = try_avg(-10, 'PSL-ISS_DIFFRACTION_AVG')
 676     ¦   #     if diff_pwr >= diff_high:
 677     ¦   #         yield "Diffracted power is high"
 678     ¦   # elif diff_now < diff_low:
 679     ¦   #     diff_pwr = try_avg(-10, 'PSL-ISS_DIFFRACTION_AVG')
 680     ¦   #     if diff_pwr <= diff_high:
 681     ¦   #         yield "Diffracted power is low"
 682     ¦   if diff_now > diff_high:
 683     ¦   ¦   yield "Diffracted power high"
 684     ¦   elif diff_now < diff_low:
 685     ¦   ¦   yield "Diffracted power low"
 686