Well it had to happen...

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rob smith Crowdfunding Project Donor*Special Project $75 donorSpecial Project $250 donor
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Message 1576054 - Posted: 22 Sep 2014, 17:20:16 UTC

Sooner or later one of my crunchers was bound to be drawn against a pair of "King Corrupters" - those crunchers that return a very high proportion of invalid results:
http://setiathome.berkeley.edu/workunit.php?wuid=1596624815
The two conspirators have about 1000 invalids between them, and I bet they are pleased with their high rate of turn-around......
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Message 1576093 - Posted: 22 Sep 2014, 18:13:49 UTC

About as bad as those NV card users that return nothing but -9 overflows.
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Message 1576101 - Posted: 22 Sep 2014, 18:30:23 UTC - in response to Message 1576054.  

Sooner or later one of my crunchers was bound to be drawn against a pair of "King Corrupters" - those crunchers that return a very high proportion of invalid results:
http://setiathome.berkeley.edu/workunit.php?wuid=1596624815
The two conspirators have about 1000 invalids between them, and I bet they are pleased with their high rate of turn-around......

It's funny, I was just commenting yesterday in Message 1575822 as to whether or not this problem had ever been addressed. A bit of research and I found it hadn't. I've actually got a list of 11 of these hosts w/ ATI GPUs that are corrupting the science database every time they match up against one another. They are 6062303, 5744165, 6228988, 6772486, 5440804, 6901854, 6836000, 6755483, 6929369, 6936833, and 6156050. There are probably more, but I quit tracking them back in February when it became obvious that the project admins didn't care about the corruption.

About as bad as those NV card users that return nothing but -9 overflows.

Actually, this is much worse because they're validating bad results against each other, causing good results to be thrown out.
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Message 1576168 - Posted: 22 Sep 2014, 20:03:27 UTC - in response to Message 1576101.  

About as bad as those NV card users that return nothing but -9 overflows.

Actually, this is much worse because they're validating bad results against each other, causing good results to be thrown out.

Exact same issue as before. When it was brought up a few years ago it was two NV GPUs that trashed their work validating against each other. With the good CPU result being tossed out. Which does still happen btw.
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Message 1576185 - Posted: 22 Sep 2014, 20:31:14 UTC

I've been watching my inconclusives and made an observation. Since ramping up production as winter approaches my pending WUs have doubled whereas my inconclusives have gone up by a factor of 5.
Assuming that I'm not generating invalids (and when I click through on my inconclusive wingman I see lots of invalids so it's probably not me) I guess that means the invalids have a comparatively fast turnaround time. Does that mean they are more likely to validate against each other?
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Message 1576225 - Posted: 22 Sep 2014, 21:46:23 UTC - in response to Message 1576185.  

I've been watching my inconclusives and made an observation. Since ramping up production as winter approaches my pending WUs have doubled whereas my inconclusives have gone up by a factor of 5.
Assuming that I'm not generating invalids (and when I click through on my inconclusive wingman I see lots of invalids so it's probably not me) I guess that means the invalids have a comparatively fast turnaround time. Does that mean they are more likely to validate against each other?

In a way the hosts trashing work do have a higher chance of finding another host trashing work to generate a false valid result. However with the large number of hosts out there it doesn't happen very often. The two machine listed in the OP are running a rate of about 3% valid. I didn't check to see if any of their valid tasks are truly valid, but given the low numbers, of 8 & 28, I expect not.
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Message boards : Number crunching : Well it had to happen...


 
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