Some screenies from 21:10 - 21:50 approx Oslo (GMT +2) Saturday 30th, 2008.

Message boards : Number crunching : Some screenies from 21:10 - 21:50 approx Oslo (GMT +2) Saturday 30th, 2008.
Message board moderation

To post messages, you must log in.

AuthorMessage
Fili

Send message
Joined: 30 Aug 07
Posts: 6
Credit: 32,413
RAC: 0
Norway
Message 803474 - Posted: 30 Aug 2008, 20:23:06 UTC

Between 21:10 and 21:50 approx GMT+2 I noticed some sudden change in the frequency block widths being displayed on the client screen, up to over an inch wide in a more uniform fashion than I've ever seen.

Example;


The varations in frequency block width lasted for 1-3 displays, before reverting back to normal width.
All this occured within approximately 1-5 minute intervals.
The widest blocks were displayed at 21:36 and 21:37 GMT+2.

I can provide full detailed information, as well as more detailed pictures and current sky position if necessary.

If this isn't something completely usual, I'd love to get info how to forward this, if it has any relevance at all.

Thanks in advance.

-Fili


ID: 803474 · Report as offensive
Profile Keck_Komputers
Volunteer tester
Avatar

Send message
Joined: 4 Jul 99
Posts: 1575
Credit: 4,152,111
RAC: 1
United States
Message 803604 - Posted: 31 Aug 2008, 6:36:30 UTC

The app runs at several different bandwidths or dispersion levels. Some levels can not be processed in some tasks. So it is probably nothing really unusual, just you have not noticed it before.
BOINC WIKI

BOINCing since 2002/12/8
ID: 803604 · Report as offensive
Fili

Send message
Joined: 30 Aug 07
Posts: 6
Credit: 32,413
RAC: 0
Norway
Message 803660 - Posted: 31 Aug 2008, 12:26:38 UTC

Thanks for the reply.

You're probably right, as processing power needs would ^x at an alarming rate if all frequency bandwidths were to be maintained at a constant rate all the time.

I noticed the bandwiths were particularly wide when a new data chunk underwent processing. (at 0.0->0.1%).

Cheers.
ID: 803660 · Report as offensive
Profile ML1
Volunteer moderator
Volunteer tester

Send message
Joined: 25 Nov 01
Posts: 20435
Credit: 7,508,002
RAC: 20
United Kingdom
Message 803690 - Posted: 31 Aug 2008, 14:47:12 UTC - in response to Message 803660.  
Last modified: 31 Aug 2008, 14:48:06 UTC

... I noticed the bandwiths were particularly wide when a new data chunk underwent processing. (at 0.0->0.1%).

I'm not sure what you mean by that...

The s@h client runs through a whole series of searches for pulses and gaussians and all at various drift rates depending on the angle range (AR) that the telescope swept across the sky whilst that WU was being recorded. The different mix of tests for a WU for a particular AR greatly affects how long a host computer takes to run through that WU. Hence some of the interest that the credits fanatics have for what "AR" a WU has.

Note that seti is all a 'best guess' at what might be found and what might be distinguishable as 'artificial' to indicate "ET".

Meanwhile, this is a fantastic project in itself involving very many people with various discoveries waiting to be found aswel as ET.

Keep searchin',
Martin
See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)
ID: 803690 · Report as offensive
Fili

Send message
Joined: 30 Aug 07
Posts: 6
Credit: 32,413
RAC: 0
Norway
Message 803759 - Posted: 31 Aug 2008, 17:56:31 UTC - in response to Message 803690.  
Last modified: 31 Aug 2008, 18:04:22 UTC

... I noticed the bandwiths were particularly wide when a new data chunk underwent processing. (at 0.0->0.1%).

I'm not sure what you mean by that...


Sorry for the large, and 2d-like display of the image, but here's an example taken from the midst of a chunk even, and not at the very start as I mentioned before.

The bands of each frequency are very wide, opposed to more normal diplays, where you can see as many as 500-700 individual frequency bands (guesstimate). This is what gained my initial interest in the phenomenon.


ID: 803759 · Report as offensive
Profile ML1
Volunteer moderator
Volunteer tester

Send message
Joined: 25 Nov 01
Posts: 20435
Credit: 7,508,002
RAC: 20
United Kingdom
Message 803773 - Posted: 31 Aug 2008, 19:00:55 UTC - in response to Message 803759.  
Last modified: 31 Aug 2008, 19:03:17 UTC

... I noticed the bandwiths were particularly wide when a new data chunk underwent processing. (at 0.0->0.1%).

I'm not sure what you mean by that...

Sorry for the large, and 2d-like display of the image, but here's an example taken from the midst of a chunk...

Good clear example, thanks.

The bands of each frequency are very wide, opposed to more normal diplays, where you can see as many as 500-700 individual frequency bands (guesstimate). This is what gained my initial interest in the phenomenon.

Analysis screenshot

Oh that's easy... And completely normal. Usually, that step is soo quick that I guess most people won't notice...

Look at the frequency resolution for that part of the search. You're on the very fast 1200Hz step. The analysis also runs through much finer steps which is what you're more familiar with seeing.

See:

What is the Screensaver doing NOW?

How SETI@Home Works

Fast Fourier Transform


Good question there! Hope that helps.

Happy crunchin',
Martin

(Not had the "screensaver" on for so long that almost forgot what it looks like!)
See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)
ID: 803773 · Report as offensive

Message boards : Number crunching : Some screenies from 21:10 - 21:50 approx Oslo (GMT +2) Saturday 30th, 2008.


 
©2024 University of California
 
SETI@home and Astropulse are funded by grants from the National Science Foundation, NASA, and donations from SETI@home volunteers. AstroPulse is funded in part by the NSF through grant AST-0307956.