We have just started the tests of a new application. The main goal is to analyse
the possibility of observational detection of quark stars. These objects are
composed of quarks, i.e. particles smaller than neutron or proton. Quark stars are
nearly similar to neutron stars, but we may observe their impact on stellar
populations.

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Właśnie uruchomiliśmy nową aplikację. Jej głównym celem jest analiza możliwości
obserwacyjnej detekcji gwiazd kwarkowych. Te obiekty składają się z kwarków,
czyli cząstek mniejszych niż neutrony czy protony. Gwiazdy kwarkowe są prawie
identyczne z gwiazdami neutronowymi, ale jest możliwe wyznaczenie ich wpływu na
populacje gwiazdowe

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Grzegorz Wiktorowicz
National Astronomical Observatories,
Chinese Academy of Sciences

QuarkStars application can use up to 350MB hard disk space in temporary files.

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Krzysztof 'krzyszp' Piszczek

Member of Radioactive@Home team
My Patreon profile
Universe@Home on YT

Is this new application compatible with Raspberry devices? If not I will have to create a separate profile for it. It did say that linux under the applications page, but just want to make sure.

Thank you

At the moment - isn't.

We have to make some batches first and look at results before we do app compilation for Android and Raspberry devices..

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Krzysztof 'krzyszp' Piszczek

Member of Radioactive@Home team
My Patreon profile
Universe@Home on YT

It looks like I started getting these around 11am EST. I should get to some of them by tomorrow.

It seems like some units are getting sent out to quite a few users well before the deadline:
http://universeathome.pl/universe/workunit.php?wuid=6189406
http://universeathome.pl/universe/workunit.php?wuid=6255363

I've had 2 of these, both were cancelled by the server, any idea why?

Pete

I've had 2 of these, both were cancelled by the server, any idea why?

If you look at your Work Units that were cancelled by server, you will probably find that they were successfully completed by two other crunchers. That is what happens with projects that use a quorum, where two users must receive a work unit to validate against each other. There is always a time limit, and if one user does not return the result soon enough, they send it out to a third user (you in this case). Then, if the one user returns it before you can get to it, the server sends out an abort to your machine, so you don't waste time on it.

There may be other scenarios where that occurs, but I see that commonly on other projects, though it is occurring more often here. Probably the time limits have been set rather short on Universe.

I've had 2 of these, both were cancelled by the server, any idea why?

If you look at your Work Units that were cancelled by server, you will probably find that they were successfully completed by two other crunchers. That is what happens with projects that use a quorum, where two users must receive a work unit to validate against each other. There is always a time limit, and if one user does not return the result soon enough, they send it out to a third user (you in this case). Then, if the one user returns it before you can get to it, the server sends out an abort to your machine, so you don't waste time on it.

There may be other scenarios where that occurs, but I see that commonly on other projects, though it is occurring more often here. Probably the time limits have been set rather short on Universe.

Correct.
Also, with new application server always more carefully and sends third WU bit faster then usually.

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Krzysztof 'krzyszp' Piszczek

Member of Radioactive@Home team
My Patreon profile
Universe@Home on YT

A third WU? Try 10!
http://universeathome.pl/universe/workunit.php?wuid=6189406

Duplicates 2 through 9 were sent within 1 hour of each other. How much as 'a bit faster'?

Look at CPU times for extra WU's. All of them doesn't take any CPU time at all.
I'm sure that with more WU's situation with them stabilise. (Anyway, on my hosts this doesn't happened).

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Krzysztof 'krzyszp' Piszczek

Member of Radioactive@Home team
My Patreon profile
Universe@Home on YT

I am guessing here that due to the reduced run time for Quarkstars against BHSpin (in my case it is over 2,000 seconds less), the credit has now been reduced accordingly from 333.33 to 250.00 per work unit.

Conan

Seems roughly inline with BHSpin v1 PPD except for the BHSpin tasks with 10 in the name. Those are still way too long.

Will there be another tasks for this application? Or maybe it was just a single shot?

Yes, we plan to develop this project further!

Quark Stars have been proposed to explain observations of very massive neutron stars, but these objects are hardly distinguishable from each other. The population studies are necessary, which will be probably available soon with Square Kilometre Array (SKA). However, a lot of theoretical study have to be done before any information may be dug out from observations. This is the goal of Quark Star application. Nevertheless, we are pioneers in such studies so a lot of tests is yet in front of us, before a large scale computation could be started.

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Grzegorz Wiktorowicz
National Astronomical Observatories,
Chinese Academy of Sciences

Thanks for info Grzegorz. That sounds very interesting.