Re: How to debug X lockup (advice from gurus wanted)
On 08/30/2011 09:24 PM, stan wrote: On Mon, 29 Aug 2011 21:06:29 +0200 Roberto Ragusa m...@robertoragusa.it wrote: Hi, it sometimes happens to me that X completely locks up, while the machine is still alive on the network. This is on F14, untainted kernel, nouveau driver, no 3D used, KDE desktop on a 32-bit machine with 8GiB RAM and PAE kernel. It typically happens when something is going to be drawn on the screen (a window pops up or virtual desktop change). I would like to open a bug, but I'm not able to attach any kind of usable log; dmesg says nothing, all I can say is that the screen remains frozen (including the pointer), the X server and the kernel keep doing some SIG ALRM stuff and any attempt to access the X server stalls the command (xrandr or xset, for example), in a Ctrl-C responsive way. Any idea? I had this problem in F14 while using the stock kernel. When I compiled a custom kernel it went away. While I made *many* changes, I think the one that mattered was turning off SMP on my single core system. I suspect, without proof, that the SMP code was occasionally causing a race condition, and a deadlock. Other possible causes for fix: moved to pre-emptable desktop, reserved 128 K low memory for kernel, moved to deadline scheduler. You could open a bug against the kernel, but it has moved on so far that it will probably languish. [now crossposting fedora, fedora-devel] Hmmm, turning off SMP is not realistic, as this laptop has a Core 2 Duo. I had been compiling my kernels until many years ago, and I would like to stay with the distro's kernel. I hope that upgrading to F15/F16 will mix things up and solve this in some way. Opening a bug seems a waste of time. I'm cross-posting to fedora-devel, in case someone can suggest how to collect useful info to open a kernel bug. Thanks. -- Roberto Ragusamail at robertoragusa.it -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
Re: How to debug X lockup (advice from gurus wanted)
On Mon, 29 Aug 2011 21:06:29 +0200 Roberto Ragusa m...@robertoragusa.it wrote: Hi, it sometimes happens to me that X completely locks up, while the machine is still alive on the network. This is on F14, untainted kernel, nouveau driver, no 3D used, KDE desktop on a 32-bit machine with 8GiB RAM and PAE kernel. It typically happens when something is going to be drawn on the screen (a window pops up or virtual desktop change). I would like to open a bug, but I'm not able to attach any kind of usable log; dmesg says nothing, all I can say is that the screen remains frozen (including the pointer), the X server and the kernel keep doing some SIG ALRM stuff and any attempt to access the X server stalls the command (xrandr or xset, for example), in a Ctrl-C responsive way. Any idea? I had this problem in F14 while using the stock kernel. When I compiled a custom kernel it went away. While I made *many* changes, I think the one that mattered was turning off SMP on my single core system. I suspect, without proof, that the SMP code was occasionally causing a race condition, and a deadlock. Other possible causes for fix: moved to pre-emptable desktop, reserved 128 K low memory for kernel, moved to deadline scheduler. You could open a bug against the kernel, but it has moved on so far that it will probably languish. -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
How to debug X lockup (advice from gurus wanted)
Hi, it sometimes happens to me that X completely locks up, while the machine is still alive on the network. This is on F14, untainted kernel, nouveau driver, no 3D used, KDE desktop on a 32-bit machine with 8GiB RAM and PAE kernel. It typically happens when something is going to be drawn on the screen (a window pops up or virtual desktop change). I would like to open a bug, but I'm not able to attach any kind of usable log; dmesg says nothing, all I can say is that the screen remains frozen (including the pointer), the X server and the kernel keep doing some SIG ALRM stuff and any attempt to access the X server stalls the command (xrandr or xset, for example), in a Ctrl-C responsive way. This is happening on different kernel revisions. This laptop is perfectly stable and it sometimes takes a few weeks to show the problem (using suspend during the night). If I do a fresh reboot there is a high probability of a lockup in a mater of minutes/hours. Just as if there were lucky and unlucky reboots (important stuff being placed in memory areas which is easily corrupted?). Another data point: this laptop sometimes fails to suspend properly (remains frozen). In any case the last frozen-X event happened today before any attempt to suspend, so I can not blame the BIOS and ACPI parts. Any idea? -- Roberto Ragusamail at robertoragusa.it -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
