Results 1 to 10 of 10

Thread: Milkyway: bypassing server set cache limits

  1. #1
    Diamond Member
    Join Date
    October 24th, 2010
    Posts
    5,743

    Milkyway: bypassing server set cache limits

    While we appreciate everyone wanting to crunch more MilkyWay@Home by increasing their cache limits; this is part of the reason why we've had so many server problems lately with an unresponsive validator. Mainly, our machine/database is not fast enough to keep up with the additional amount of workunits this is causing in the database. So if anyone is modifying their BOINC client to artificially increase their cache we're asking you to stop so the project will be more stable (until we can further improve our hardware). A few of the really offending clients (who have cached 1k+ workunits) are being banned as they haven't responded to us, and they're hurting everyones ability to crunch the project as a whole.
    So in short, we need you guys to work with us as we're working with limited hardware that can't handle more than 500k+ workunits at a time -- our cache is low partially for this reason. Second, as we've said in a bunch of previous threads in the past, due to the nature of the science we're doing at the project we need a low cache because this really improves the quality of the work you guys report.
    As you (hopefully) know by now, we search for structure and try to optimize parameters to fit that structure within the Milky Way galaxy. And lately we've been also doing N-Body simulation of the formation of those structures. What your workunits are doing is trying to find the optimal set of parameters for those N-Body simulations to end up best representing our sky survey data or to fit those different structures (like dwarf galaxy tidal streams) from that data.
    To do this, we use strategies which mimic evolution. The server keeps track of a population of good potential solutions to these problems, and then generates workunits by mutating some solutions, and using others to create offspring. You guys crunch the data and return the result -- if it's a good one we insert it into the population which improves as a whole. Over time, we get very very good solutions which aren't really possible using other deterministic approaches.
    If people have large caches, that means the work they're crunching can come from very old versions of those populations which have since evolved quite a bit away from where they were when the user filled up their cache. When they return the results there's a lower chance for the results to improve the population of results we're currently working with.
    So that's why our cache is so low, and we'd really appreciate it if you worked with us on this. There are other great BOINC projects out there which can help fill in missing crunch time when we go down, and the BOINC client can definitely handle running more than one at a time. So it might not be too bad to explore some of the other great research going on out there. :)
    Thanks again for your time and understanding,
    --Travis

    More...

  2. #2
    Silver Member
    Dandasarge's Avatar
    Join Date
    December 3rd, 2010
    Location
    Orlando, FL
    Posts
    586

    Re: Milkyway: bypassing server set cache limits

    no ones is getting ban I hope?
    People do not grow old no matter how long we live. We never cease to stand like curious children before the great Mystery into which we


  3. #3
    Administrator
    STMahlberg's Avatar
    Join Date
    November 1st, 2010
    Location
    AREA 51
    Posts
    1,533

    Re: Milkyway: bypassing server set cache limits

    Quote Originally Posted by Dandasarge View Post
    no ones is getting ban I hope?
    I hate to display my ignorance but I have no idea what Travis is talking about so I'm pretty sure I'm safe... I think.
    "My god! Do we really suck, or is this guy really that good?" - Mr Hertz - Shoot 'Em Up






  4. #4
    Cappy
    Guest

    Re: Milkyway: bypassing server set cache limits

    well you can fudge with your cpu settings in Boinc to make it look like your running

    a 16 core,, 32 core , 48 core lol however big you want your cruncher to be

    and when you change the cpu count in Boinc that also adjusts the cashe amout.....

    so you go from their standard quad core and they limit you to 12 wu's... well if you set the cpu count in boinc to 2 well now you have a dual quad core lol when in reality you have just a quad core

    hope this made sence theres alot of little tricks and tweeks you can do but if you

    abuse those and then people start to notice well then its YOUR bad..... the idea is to

    stay UNDER the radar so not to be noticed lol....

  5. #5
    Gold Member
    Slicker's Avatar
    Join Date
    October 25th, 2010
    Location
    South of Cheeseland
    Posts
    1,253

    Re: Milkyway: bypassing server set cache limits

    Hypothetically speaking... to stay under the radar, one must also alter the boinc client (e.g. you download the boinc client source code, change it, and compile it yourself) so that it not only reports more cpus, but also changes the description, the flops estimates, etc. so that the project truly thinks your machine is a V8, V16, etc. The problem with doing that is that when you connect to other projects, they will send way too much work for your machine to complete.
    Spring 2008 Race: (1st Place)

  6. #6
    Harley
    Guest

    Re: Milkyway: bypassing server set cache limits

    I sure glad this fixed the problems. This is getting old. Maybe its time to move on!

  7. #7
    Cappy
    Guest

    Re: Milkyway: bypassing server set cache limits

    Quote Originally Posted by Slicker View Post
    Hypothetically speaking... to stay under the radar, one must also alter the boinc client (e.g. you download the boinc client source code, change it, and compile it yourself) so that it not only reports more cpus, but also changes the description, the flops estimates, etc. so that the project truly thinks your machine is a V8, V16, etc. The problem with doing that is that when you connect to other projects, they will send way too much work for your machine to complete.
    ya i know i gave the laymens explanation

    keepin it simple

  8. #8
    Gold Member
    joker's Avatar
    Join Date
    October 25th, 2010
    Location
    HELL
    Posts
    1,600

    Re: Milkyway: bypassing server set cache limits

    Does this have anything to do with MW not paying out any credits for the better part of the last 2 days?

  9. #9
    Platinum Member
    Maxwell's Avatar
    Join Date
    October 25th, 2010
    Location
    Everett, WA
    Posts
    3,300

    Re: Milkyway: bypassing server set cache limits

    Quote Originally Posted by joker View Post
    Does this have anything to do with MW not paying out any credits for the better part of the last 2 days?
    I think that's a separate, but potentially related issue. The teams section of the database crashed, so teams are all wonky and stats have not been exported. However, if you check your account, you are still getting the credit...

    http://milkyway.cs.rpi.edu/milkyway/...ad.php?id=2185
    Last edited by Maxwell; 01-26-11 at 08:39 PM.

  10. #10
    Gold Member
    joker's Avatar
    Join Date
    October 25th, 2010
    Location
    HELL
    Posts
    1,600

    Re: Milkyway: bypassing server set cache limits

    Thx for the info Max.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •