Re: Re: Coolest Mathematica trick you'll see this month
- To: mathgroup at smc.vnet.net
- Subject: [mg96860] Re: [mg96791] Re: Coolest Mathematica trick you'll see this month
- From: Chris Pemberton <cjpembo at gmail.com>
- Date: Thu, 26 Feb 2009 07:56:29 -0500 (EST)
- References: <go0j6q$n2t$1@smc.vnet.net> <200902250902.EAA15595@smc.vnet.net>
ragfield wrote: > On Feb 24, 4:46 am, Chris Pemberton <cjpe... at gmail.com> wrote: > >> I use Linux on my machines and enjoy helping other Archlinux users in >> the online forums. A fellow Arch user was having issues with >> Mathematica 7. He was plotting a 3D parametric equation and >> experiencing a sustained high processor load on this laptop; only >> killing the kernel would allow the CPU to idle down. He found that the >> laptop's accelerometer kernel driver was eating nearly 30% of the CPU >> time.... You'll just have to read the forum to see the rest! >> >> http://bbs.archlinux.org/viewtopic.php?id=65916 >> >> Can any Windows or Mac users duplicate this? Or is this a Linux-only >> "feature"? Or maybe this is well-known and I'm just late in finding ou= >> > t? > > On Linux, Mathematica will treat devices at /dev/input/js0 through jsN > as controllers. As you discovered, apparently this laptop's > accelerometer masquerades as a joystick. The high CPU usage is caused > by the driver sending many updates to the device file descriptor, > which Mathematica watches and does work whenever the values change. > > This can be disabled by adding the name of the controller (as returned > by ControllerInformation[]) to the value list for the undocumented > option "DisableControllers": > > SetOptions[$FrontEnd, DisableControllers -> Prepend > [DisableControllers /. Options[$FrontEnd, DisableControllers], "DEVICE > NAME HERE"]] > > -Rob > > > Thanks for the info. I'll pass it along. That will be easier than unloading the accelerometer module.
- References:
- Re: Coolest Mathematica trick you'll see this month guaranteed
- From: ragfield <ragfield@gmail.com>
- Re: Coolest Mathematica trick you'll see this month guaranteed