Re: idle=poll burns my box [was Re: 2.6.22-rc2-mm1]
On Fri, 25 May 2007 23:20:25 +0200 "J.A. Magallón" <[EMAIL PROTECTED]> wrote: > Is idle=poll a quick and dirty way to burn your box in flames ? yep ;) It makes the CPU(s) busy-wait when they have nothing else to do. It was originally added as a thing to maybe save a few cycles of latency in responding to interrupts. It's now useful as a trick to prevent oprofile from producing confusing numbers. I don't think it has any other uses. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
idle=poll burns my box [was Re: 2.6.22-rc2-mm1]
On Wed, 23 May 2007 00:42:33 -0700, Andrew Morton <[EMAIL PROTECTED]> wrote: > > ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.22-rc2/2.6.22-rc2-mm1/ > Don't know if it's specific to this kernel, but as I have realized it now... I booted with idle=poll to check some issues (with nvidia driver, btw). And suddenly I noticed my box was running near 80ºC hot. I pulled out the lid, an try to see what happened. In short, idle=poll rises the temperature about 20ºC. I have an ASUS PC-DL mobo, with a couple Xeon Northwood with HypertThreading at 2.4 GHz, for a total of 4 threads. If I boot the box with idle=poll, and let it doing _nothing_ but staring at the gnome desktop, I get this temperatures: (Time,VRM,CPU0,CPU1) (wihtout the side cover, remember...) 15:46 64 56 54 15:55 70 60 56 16:02 71 62 57 If I reboot without idle=poll, the box colds quickly: 16:07 58 52 48 16:12 50 43 42 16:15 49 42 41 I I put the box to do some multithreaded render, so all four cores stay above 98% usage, the box warms again: 16:17 51 43 42 16:24 67 57 54 16:28 70 60 56 16:30 72 61 57 16:37 72 61 56 And as soon as I stop the work, it colds again: 16:41 71 60 56 16:42 64 56 52 16:43 60 54 50 16:45 55 48 46 16:46 53 46 44 Left alone for awhile, it stays at 46 39 39 (for VRM and both CPUs, as I said). Is idle=poll a quick and dirty way to burn your box in flames ? To warm your cpu doing nothing ? Summer is coming, but this... Any ideas ? -- J.A. Magallon \ Software is like sex: \ It's better when it's free Mandriva Linux release 2008.0 (Cooker) for i586 Linux 2.6.21-jam03 (gcc 4.1.2 20070302 (4.1.2-1mdv2007.1)) SMP PREEMPT 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
idle=poll burns my box [was Re: 2.6.22-rc2-mm1]
On Wed, 23 May 2007 00:42:33 -0700, Andrew Morton [EMAIL PROTECTED] wrote: ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.22-rc2/2.6.22-rc2-mm1/ Don't know if it's specific to this kernel, but as I have realized it now... I booted with idle=poll to check some issues (with nvidia driver, btw). And suddenly I noticed my box was running near 80ºC hot. I pulled out the lid, an try to see what happened. In short, idle=poll rises the temperature about 20ºC. I have an ASUS PC-DL mobo, with a couple Xeon Northwood with HypertThreading at 2.4 GHz, for a total of 4 threads. If I boot the box with idle=poll, and let it doing _nothing_ but staring at the gnome desktop, I get this temperatures: (Time,VRM,CPU0,CPU1) (wihtout the side cover, remember...) 15:46 64 56 54 15:55 70 60 56 16:02 71 62 57 If I reboot without idle=poll, the box colds quickly: 16:07 58 52 48 16:12 50 43 42 16:15 49 42 41 I I put the box to do some multithreaded render, so all four cores stay above 98% usage, the box warms again: 16:17 51 43 42 16:24 67 57 54 16:28 70 60 56 16:30 72 61 57 16:37 72 61 56 And as soon as I stop the work, it colds again: 16:41 71 60 56 16:42 64 56 52 16:43 60 54 50 16:45 55 48 46 16:46 53 46 44 Left alone for awhile, it stays at 46 39 39 (for VRM and both CPUs, as I said). Is idle=poll a quick and dirty way to burn your box in flames ? To warm your cpu doing nothing ? Summer is coming, but this... Any ideas ? -- J.A. Magallon jamagallon()ono!com \ Software is like sex: \ It's better when it's free Mandriva Linux release 2008.0 (Cooker) for i586 Linux 2.6.21-jam03 (gcc 4.1.2 20070302 (4.1.2-1mdv2007.1)) SMP PREEMPT 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0 - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: idle=poll burns my box [was Re: 2.6.22-rc2-mm1]
On Fri, 25 May 2007 23:20:25 +0200 J.A. Magallón [EMAIL PROTECTED] wrote: Is idle=poll a quick and dirty way to burn your box in flames ? yep ;) It makes the CPU(s) busy-wait when they have nothing else to do. It was originally added as a thing to maybe save a few cycles of latency in responding to interrupts. It's now useful as a trick to prevent oprofile from producing confusing numbers. I don't think it has any other uses. - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/