Arecibo Overflow Tasks Run With CUDA Special App Sometimes Filled With Triplets Only

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Message 1953287 - Posted: 1 Sep 2018, 23:16:49 UTC
Last modified: 1 Sep 2018, 23:19:09 UTC

This thread is to help research why some Arecibo Tasks end up Invalid with a count of 30 Triplets. This is a typical task;
https://setiathome.berkeley.edu/result.php?resultid=6930449358
Download http://boinc2.ssl.berkeley.edu/sah/download_fanout/1a5/27au18aa.29125.12028.8.35.0


WU true angle range is :  0.395544
Sigma 3
Thread call stack limit is: 1k
Find triplets Cuda kernel encountered too many triplets, or bins above threshold, reprocessing this PoT on CPU... err = 1
Triplet: peak=11.73312, time=104.3, period=0.003277, d_freq=1420003662.11, chirp=0, fft_len=8 
Triplet: peak=10.33696, time=6.789, period=1.658, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.18257, time=12.07, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.15186, time=12.27, period=0.4145, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.08709, time=12.18, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.18257, time=12.18, period=0.1122, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.18257, time=12.27, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.18257, time=12.48, period=0.4145, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=10.99139, time=12.47, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=10.32397, time=12.48, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.08709, time=12.39, period=0.09503, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=10.99139, time=12.68, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.08631, time=12.69, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.2429, time=12.67, period=4.958, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=10.15737, time=12.91, period=4.465, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.28831, time=12.07, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.25731, time=12.27, period=0.4145, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.25731, time=12.39, period=0.5267, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.19192, time=12.18, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.06544, time=12.26, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.06544, time=12.47, period=0.4145, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.28831, time=12.18, period=0.1122, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.28831, time=12.27, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.28831, time=12.48, period=0.4145, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.09532, time=12.47, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=10.42159, time=12.48, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.19192, time=12.39, period=0.09503, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.09532, time=12.68, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=11.19114, time=12.69, period=0.2073, d_freq=1419995117.19, chirp=0, fft_len=8 
Triplet: peak=9.856684, time=17.88, period=0.503, d_freq=1419995117.19, chirp=0, fft_len=8 
SETI@Home Informational message -9 result_overflow
NOTE: The number of results detected equals the storage space allocated.

Best spike: peak=7.97499, time=84.19, d_freq=1419995117.19, chirp=0, fft_len=8 
Best autocorr: peak=0, time=-2.124e+11, delay=0, d_freq=0, chirp=0, fft_len=0 
Best gaussian: peak=0, mean=0, ChiSq=0, time=-2.124e+11, d_freq=0,
	score=-12, null_hyp=0, chirp=0, fft_len=0 
Best pulse: peak=0, time=-2.124e+11, period=0, d_freq=0, score=0, chirp=0, fft_len=0 
Best triplet: peak=11.73312, time=104.3, period=0.003277, d_freq=1420003662.11, chirp=0, fft_len=8 
Spike count:    0
Autocorr count: 0
Pulse count:    0
Triplet count:  30
Gaussian count: 0

When run with a CPU App the same task looks as though;

WU true angle range is :  0.395544
Pulse: peak=0.7584873, time=6.787, period=0.1036, d_freq=1420001220.7, score=1.075, chirp=0, fft_len=8 
D:	threshold 0.0007635616; unscaled peak power: 0.0007873132 exceeds threshold for 3.111%
Pulse: peak=0.1231679, time=13.57, period=0.00329, d_freq=1420001220.7, score=1.247, chirp=0, fft_len=8 
D:	threshold 0.0004870627; unscaled peak power: 0.000497881 exceeds threshold for 2.221%
Pulse: peak=0.1067214, time=20.36, period=0.00329, d_freq=1420001220.7, score=1.081, chirp=0, fft_len=8 
D:	threshold 0.000480932; unscaled peak power: 0.0004844154 exceeds threshold for 0.7243%
Pulse: peak=0.1239467, time=27.15, period=0.002878, d_freq=1420001220.7, score=1.265, chirp=0, fft_len=8 
D:	threshold 0.0004853548; unscaled peak power: 0.0004968247 exceeds threshold for 2.363%
Pulse: peak=0.7474262, time=33.93, period=0.1036, d_freq=1420001220.7, score=1.06, chirp=0, fft_len=8 
D:	threshold 0.0007508046; unscaled peak power: 0.0007692898 exceeds threshold for 2.462%
Pulse: peak=0.1214741, time=40.72, period=0.00329, d_freq=1420001220.7, score=1.23, chirp=0, fft_len=8 
D:	threshold 0.0004840197; unscaled peak power: 0.0004940243 exceeds threshold for 2.067%
Pulse: peak=0.7307431, time=47.51, period=0.1036, d_freq=1420001220.7, score=1.036, chirp=0, fft_len=8 
D:	threshold 0.0007558875; unscaled peak power: 0.0007671035 exceeds threshold for 1.484%
Pulse: peak=0.1188357, time=54.3, period=0.00329, d_freq=1420001220.7, score=1.203, chirp=0, fft_len=8 
D:	threshold 0.0004903566; unscaled peak power: 0.0004993148 exceeds threshold for 1.827%
Pulse: peak=0.1383048, time=61.08, period=0.00329, d_freq=1420001220.7, score=1.4, chirp=0, fft_len=8 
D:	threshold 0.0004821375; unscaled peak power: 0.0004994886 exceeds threshold for 3.599%
Pulse: peak=0.7744395, time=67.87, period=0.1036, d_freq=1420001220.7, score=1.098, chirp=0, fft_len=8 
D:	threshold 0.0007477313; unscaled peak power: 0.0007779845 exceeds threshold for 4.046%
Pulse: peak=0.108801, time=81.44, period=0.00329, d_freq=1420001220.7, score=1.102, chirp=0, fft_len=8 
D:	threshold 0.0004769428; unscaled peak power: 0.0004813001 exceeds threshold for 0.9136%
Pulse: peak=0.1024829, time=88.23, period=0.00329, d_freq=1420001220.7, score=1.038, chirp=0, fft_len=8 
D:	threshold 0.0004811804; unscaled peak power: 0.0004828095 exceeds threshold for 0.3386%
Pulse: peak=0.1035062, time=95.02, period=0.00329, d_freq=1420001220.7, score=1.048, chirp=0, fft_len=8 
D:	threshold 0.0004824028; unscaled peak power: 0.0004844854 exceeds threshold for 0.4317%
Pulse: peak=0.1116922, time=100.6, period=0.00329, d_freq=1420001220.7, score=1.131, chirp=0, fft_len=8 
D:	threshold 0.0004816972; unscaled peak power: 0.0004873654 exceeds threshold for 1.177%
Pulse: peak=0.1110835, time=47.51, period=0.00329, d_freq=1420002441.41, score=1.125, chirp=0, fft_len=8 
D:	threshold 0.000504872; unscaled peak power: 0.0005105332 exceeds threshold for 1.121%
Pulse: peak=0.1223215, time=67.87, period=0.00329, d_freq=1420002441.41, score=1.239, chirp=0, fft_len=8 
D:	threshold 0.0004958975; unscaled peak power: 0.0005065301 exceeds threshold for 2.144%
Pulse: peak=0.2369393, time=81.44, period=0.009869, d_freq=1420002441.41, score=1.272, chirp=0, fft_len=8 
D:	threshold 0.0005332696; unscaled peak power: 0.0005560181 exceeds threshold for 4.266%
Pulse: peak=0.1029696, time=88.23, period=0.00329, d_freq=1420002441.41, score=1.043, chirp=0, fft_len=8 
D:	threshold 0.0004986195; unscaled peak power: 0.0005005285 exceeds threshold for 0.3829%
Pulse: peak=0.1026665, time=95.02, period=0.00329, d_freq=1420002441.41, score=1.04, chirp=0, fft_len=8 
D:	threshold 0.0004966219; unscaled peak power: 0.0004983862 exceeds threshold for 0.3553%
Pulse: peak=0.1662154, time=100.6, period=0.00658, d_freq=1420002441.41, score=1.154, chirp=0, fft_len=8 
D:	threshold 0.0005205708; unscaled peak power: 0.0005306425 exceeds threshold for 1.935%
Pulse: peak=2.276725, time=6.787, period=0.2073, d_freq=1420003662.11, score=2.089, chirp=0, fft_len=8 
D:	threshold 0.001051732; unscaled peak power: 0.001649073 exceeds threshold for 56.8%
Pulse: peak=2.255812, time=13.57, period=0.2073, d_freq=1420003662.11, score=2.07, chirp=0, fft_len=8 
D:	threshold 0.001055386; unscaled peak power: 0.001644241 exceeds threshold for 55.8%
Pulse: peak=2.092395, time=20.36, period=0.2073, d_freq=1420003662.11, score=1.92, chirp=0, fft_len=8 
D:	threshold 0.00104289; unscaled peak power: 0.001543222 exceeds threshold for 47.98%
Pulse: peak=2.053007, time=27.15, period=0.2073, d_freq=1420003662.11, score=1.884, chirp=0, fft_len=8 
D:	threshold 0.001032697; unscaled peak power: 0.001508674 exceeds threshold for 46.09%
Pulse: peak=2.162665, time=33.93, period=0.2073, d_freq=1420003662.11, score=1.984, chirp=0, fft_len=8 
D:	threshold 0.001047343; unscaled peak power: 0.001585028 exceeds threshold for 51.34%
Pulse: peak=2.028072, time=40.72, period=0.2073, d_freq=1420003662.11, score=1.861, chirp=0, fft_len=8 
D:	threshold 0.001039219; unscaled peak power: 0.001505802 exceeds threshold for 44.9%
Pulse: peak=1.875426, time=47.51, period=0.2073, d_freq=1420003662.11, score=1.721, chirp=0, fft_len=8 
D:	threshold 0.001064652; unscaled peak power: 0.00146489 exceeds threshold for 37.59%
Pulse: peak=1.51875, time=54.3, period=0.1036, d_freq=1420003662.11, score=2.153, chirp=0, fft_len=8 
D:	threshold 0.0008719336; unscaled peak power: 0.001287753 exceeds threshold for 47.69%
Pulse: peak=2.467272, time=61.08, period=0.2073, d_freq=1420003662.11, score=2.264, chirp=0, fft_len=8 
D:	threshold 0.001040924; unscaled peak power: 0.001727038 exceeds threshold for 65.91%
Pulse: peak=1.950807, time=67.87, period=0.2073, d_freq=1420003662.11, score=1.79, chirp=0, fft_len=8 
SETI@Home Informational message -9 result_overflow
NOTE: The number of results detected equals the storage space allocated.

Best spike: peak=0, time=-2.124e+11, d_freq=0, chirp=0, fft_len=0 
Best autocorr: peak=0, time=-2.124e+11, delay=0, d_freq=0, chirp=0, fft_len=0 
Best gaussian: peak=0, mean=0, ChiSq=0, time=-2.124e+11, d_freq=0,
	score=-12, null_hyp=0, chirp=0, fft_len=0 
Best pulse: peak=0.4117213, time=54.3, period=0.00329, d_freq=1420003662.11, score=4.169, chirp=0, fft_len=8 
Best triplet: peak=0, time=-2.124e+11, period=0, d_freq=0, chirp=0, fft_len=0 

Spike count:    0
Autocorr count: 0
Pulse count:    30
Triplet count:  0
Gaussian count: 0
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Message 1953291 - Posted: 1 Sep 2018, 23:36:19 UTC
Last modified: 1 Sep 2018, 23:40:39 UTC

To Download the task from SETI in Linux you need to have Libre Office installed with the Macro Security Lowed.
Tools/Options/Security/Macro Security/Security Level = Low
Download the SETI Fanout Generator http://lunatics.kwsn.info/index.php?action=downloads;sa=view;down=415

Double-Click the Fanout Generator
Copy and paste the WU name into the Top Left box
The first Generated address should be the Correct one for SETI Main
Copy and paste the URL into FireFox and Download the task, also post the URL to this thread.
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Message 1953292 - Posted: 1 Sep 2018, 23:44:09 UTC - in response to Message 1953287.  
Last modified: 1 Sep 2018, 23:45:50 UTC

A noise bomb is a noisebomb.

It filled with results (probable signal candidates).

It is about of reporting order.
Which one of them to stop recording 30 of them and
where to start printing/writing them (max 30) to a file to submit to the servers.

Every one of found signals from a noise bomb could be claimed "valid"!

Ones, Tens, Hundreds, Thousands, Tens of thousands ...

So No help.

Petri.
To overcome Heisenbergs:
"You can't always get what you want / but if you try sometimes you just might find / you get what you need." -- Rolling Stones
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Profile Brent Norman Crowdfunding Project Donor*Special Project $75 donorSpecial Project $250 donor
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Message 1953293 - Posted: 1 Sep 2018, 23:45:12 UTC

One from me, sorry no fanout, it's gone ..
http://setiathome.berkeley.edu/workunit.php?wuid=3116515390
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Message 1953295 - Posted: 1 Sep 2018, 23:53:38 UTC - in response to Message 1953291.  

// WAS 11 in V0.97 before b2
#define MAX_TRIPLETS_ABOVE_THRESHOLD 13
that is in pulsefind cuda code.

Someone a long time before me has decided a hard limit. 11 or 13 or some value is the maximum of number of ...
If I make that number bigger it slows down triplet finding but reports more of them. If I make that smaller it misses triplets.

Easy to fix. Make it 11. Miss the rest of them.
To overcome Heisenbergs:
"You can't always get what you want / but if you try sometimes you just might find / you get what you need." -- Rolling Stones
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Message 1953297 - Posted: 1 Sep 2018, 23:55:48 UTC - in response to Message 1953293.  

One from me, sorry no fanout, it's gone ..
http://setiathome.berkeley.edu/workunit.php?wuid=3116515390


Thanks Brent for trying!
To overcome Heisenbergs:
"You can't always get what you want / but if you try sometimes you just might find / you get what you need." -- Rolling Stones
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Message 1953298 - Posted: 1 Sep 2018, 23:59:43 UTC - in response to Message 1953297.  

So, I didn't follow that. Are you saying it's easy to fix, or, are you saying if you try to fix it the App will miss All Triplets?
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Message 1953299 - Posted: 2 Sep 2018, 0:01:32 UTC - in response to Message 1953295.  

// WAS 11 in V0.97 before b2
#define MAX_TRIPLETS_ABOVE_THRESHOLD 13
that is in pulsefind cuda code.

Someone a long time before me has decided a hard limit. 11 or 13 or some value is the maximum of number of ...
If I make that number bigger it slows down triplet finding but reports more of them. If I make that smaller it misses triplets.

Easy to fix. Make it 11. Miss the rest of them.

The problem doesn't appear to be finding the signals, it's about their classification.

GPU application Triplet count: 30
CPU application Pulse count: 30
The CPU is the reference, so the GPU needs to match it's classification of Pulses, not Triplets.
Grant
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Message 1953302 - Posted: 2 Sep 2018, 0:18:43 UTC

From another thread-
A noise bomb has so many signals that it makes a standard SW and a special SW hard to decide when to stop recording them.
The WU is processed from start to finish and the collecting part of the software has to have a limit what to store in CPU RAM.
...
Quite hard to select the "correct ones" since everything is "Correct" but only 30 can be reported.

A noise bomb is a noisebomb.


Does the CPU application always report a noise bomb as 30 pulses?
If so, set the GPU application to report noise bombs as 30 pulses also.

If the GPU application reports some noise bombs as Pulses & others as Triplets it would make sense (to me) to determine what is different about those WUs, and make the GPU application report them with the same classification.
Grant
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Message 1953303 - Posted: 2 Sep 2018, 0:24:07 UTC - in response to Message 1953299.  
Last modified: 2 Sep 2018, 0:31:51 UTC

// WAS 11 in V0.97 before b2
#define MAX_TRIPLETS_ABOVE_THRESHOLD 13
that is in pulsefind cuda code.

Someone a long time before me has decided a hard limit. 11 or 13 or some value is the maximum of number of ...
If I make that number bigger it slows down triplet finding but reports more of them. If I make that smaller it misses triplets.

Easy to fix. Make it 11. Miss the rest of them.

The problem doesn't appear to be finding the signals, it's about their classification.

GPU application Triplet count: 30
CPU application Pulse count: 30
The CPU is the reference, so the GPU needs to match it's classification of Pulses, not Triplets.


No It Does Not.

EDIT: There are 30 or more of both of them. END EDIT

There are thousands of signals in a 30/30 noise bomb, When the limit is reached the search stops. It is a noise bomb.
Some software stop at some point and some other software stop at some other point.
Crippling a parallel find requiring serial order is something that no one wants.
We're going to the future.
The after processing software or a new type of WU is needed to check that a noise bomb is a noise bomb which it is anyway.
We need no consensus of by what signals (autocorr, triplets, gaussians, pulses, spikes) or whatever is searched for.
It does not matter if any SW says it is a noise bomb and any of them agree/disagree.
It is a noise bomb.
Let the system send it to a GPU to make someone happy <3.
To overcome Heisenbergs:
"You can't always get what you want / but if you try sometimes you just might find / you get what you need." -- Rolling Stones
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Message 1953310 - Posted: 2 Sep 2018, 0:47:51 UTC - in response to Message 1953303.  
Last modified: 2 Sep 2018, 1:02:30 UTC

The CPU is the reference, so the GPU needs to match it's classification of Pulses, not Triplets.


No It Does Not.

Yes it does.


This is a scientific project, the goal of which is to try to find signs of extra-terrestrial intelligent life.
The method being used is to check for non-natural electro magnetic signals amongst all the naturally occurring ones. What they are looking for (amongst other things) are Pulses & Triplets (particular groups of pulses). The project determined & defined what qualifies as Triplets, and what qualifies as just Pulses.
Changing those definitions just because they are inconvenient to someone developing their own application isn't an option. Any 3rd party applications need to work within the definitions & limits as set by the project.

What is or isn't a Pulse or Triplet has been determined by the project, and their CPU application was developed according to those definitions. And any other applications need to conform to those definitions in order to return valid work.

Hence the results returned by any 3rd party application need to match up with those returned by the project's stock CPU application (and any stock GPU application as it should be returning the same results as the stock CPU application in order to become a stock GPU application in the first place), nose bomb or not.


EDIT- you could always present a case to Eric that what is considered a Pulse or Triplet isn't relevant when it comes to a noise bomb WU, and so not affect validation- so 30 pulses would validate against 30 Triplets no need for an extra re-issue.
However in the past the determination of Pulses/Triplets has been a good indicator of problems with hardware (anyone remember the GTX 560Ti problems?). In order to account for that a Noisy WU would validate regardless of the Pulse/Triplet determination if 3 WUs all come back as being noisy (it used to require 3 WUs in order to Validate work).

But then you would need to re-consider what constitutes a noise bomb- 10%, 40%, 100% of the WU?
Presently a work unit is considered noisy at the point 30 pulses or triplets are found. Often that occurs at the start of processing, sometimes it still occurs almost at the end. What if there are only 35 Pulses/Triplets actually in a given WU?
As you say, the GPU can quickly process a whole WU (up to the limit of available GPU/System resources). Should we stick with 30, or increase it to 60, or 120 (or higher)?
Grant
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Message 1953314 - Posted: 2 Sep 2018, 1:20:41 UTC

The nice thing about it is....
It only happens on Arecibo Tasks, and Soon (not soon enough) We will Stop receiving Arecibo Tasks and the problem will Disappear all by itself.
I say, if it can't be easily solved, then wait for it to Disappear.
It doesn't happen very often anyway, the Normal machines can go a week without seeing it. The Fastest machines may see a handful when an Arecibo File is Split.

Not worth the bother I suppose.
Bookmark this thread, if Anyone says Anything else about this problem, direct them to this thread.
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Message 1953322 - Posted: 2 Sep 2018, 2:03:52 UTC - in response to Message 1953314.  

The nice thing about it is....
It only happens on Arecibo Tasks, and Soon (not soon enough) We will Stop receiving Arecibo Tasks and the problem will Disappear all by itself.
I say, if it can't be easily solved, then wait for it to Disappear.

What if it starts to occur on different GBT files? We certainly haven't come close to doing all the different types of data that will produce.
And Parkes data when it comes online?
And what happens if Arecibo secures more funding that result in more of these noisy WUs?
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Message 1953330 - Posted: 2 Sep 2018, 2:31:25 UTC - in response to Message 1953322.  

What If, What If, What If. What If a Large Asteroid comes hurtling out of the Sun and strikes in the heart of Australia?
Well, it won't be pretty, but, there is not much that can be done beforehand. I suppose we'll have to deal with it after it happens.
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Message 1953340 - Posted: 2 Sep 2018, 3:12:21 UTC - in response to Message 1953330.  

What If, What If, What If. What If a Large Asteroid comes hurtling out of the Sun and strikes in the heart of Australia?
Well, it won't be pretty, but, there is not much that can be done beforehand. I suppose we'll have to deal with it after it happens.

True, but one of those events is much more likely than the other.
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Message 1953344 - Posted: 2 Sep 2018, 4:29:46 UTC - in response to Message 1953303.  

Hey Petri, I seem to remember some other 'special case' where the problem was solved by dropping back to serial computing.

Maybe that needs to be done here as well, if noisy because of a triplet overflow, goto serial processing.
It shouldn't be a big deal, only a few seconds more work.
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Message 1953349 - Posted: 2 Sep 2018, 7:27:22 UTC

Boincmgr could reschedule a noise bomb (any 30/30 task) to CPU. I think that would be waste of resources.

The definition of a pulse or a triplet has not changed. The special app finds valid pulses and valid triplets that are there in the WU.

There are just so many of them. 30 or more to choose from in a noise bomb. To begin with the data in a noise bomb is invalid. You can not make a valid report from invalid data. 30 anything means the WU has noise and it should be discarded and the computation stopped. Noise bombs have no usable data. They need not report anything. Just label the WU invalid.

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Message 1953353 - Posted: 2 Sep 2018, 8:00:46 UTC - in response to Message 1953349.  
Last modified: 2 Sep 2018, 8:01:47 UTC

The definition of a pulse or a triplet has not changed. The special app finds valid pulses and valid triplets that are there in the WU.

The definition has been changed if it find Pulses where the CPU application finds Triplets, or it finds Triplets where the CPU application finds Pulses. It needs to produce the same result as the reference.

To begin with the data in a noise bomb is invalid.

The data isn't invalid, it is just noisy. If it were invalid then the WU would error out.
This is what happened with that GBT file a few weeks back- the data wasn't valid, so the splitters errored out.
If the splitters produce invalid WUs, then the application Errors them out when it tries to run them (as has happened in the past).

While it may be noisy, and we can't make use of it, the data is still Valid.


You can not make a valid report from invalid data.

Of course not, it's called an Error, just as I pointed out above.


30 anything means the WU has noise and it should be discarded and the computation stopped. Noise bombs have no usable data. They need not report anything. Just label the WU invalid.

Why label something that is valid, as invalid?
If 2 applications agree that the WU is a noise bomb, and they agree on the type of noise (Pulses or Triplets) then the result is Valid & Credit is granted. If not, a 3rd WU is issued & Credit will be granted to that & the WU it matches up with. A Valid result. The one that doesn't match is Invalid, is marked as such, and receives no Credit.


Noise bombs have no usable data

For the current applications, hence they stop being processed when 30 Pulses/Triplets are found. But people should get Credit for the work they do, as long as they produce a Valid result. But If their application doesn't match the reference one, then they won't get Credit as it's not a Valid result.
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Message 1953758 - Posted: 5 Sep 2018, 2:47:49 UTC
Last modified: 5 Sep 2018, 2:56:26 UTC

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Message 1953760 - Posted: 5 Sep 2018, 2:58:09 UTC - in response to Message 1953758.  

I think all bets are off whenever the application punts the task to the cpu because of too many triplets found. This goes for the SoG app too. If the task gets shifted from the gpu to the cpu because the bins were exceeded, the task usually will go inconclusive until two hosts process it entirely on a cpu. Discounting any flavor of Mac of course.
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Message boards : Number crunching : Arecibo Overflow Tasks Run With CUDA Special App Sometimes Filled With Triplets Only


 
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