Re: PROBLEM: tickless scheduling

[Robert Hancock <hancockrwd@gmail.com>]

On 05/10/2010 06:18 PM, Donald Allen wrote:
> 1. Network file transfers and fscks stop on Toshiba netbook unless
> system receives external events
> 2. I have a new Toshiba NB305 on which I installed the beta release of
> Slackware 13.1, which provides a 2.6.33.3 kernel with the tickless
> option enabled. With this machine on my ethernet, I attempted to rsync
> my home directory to it, about 9 Gb, from a workstation that is my
> primary system (running Slackware 13). The transfer proceeded normally
> for awhile and then stopped, which I could see in the xterm on the
> workstation. I went to the netbook to see what was going on there and
> when I began typing, the transfer resumed. I ran 'top' on the netbook
> and it would freeze after a few updates, coinciding with the file
> transfer pausing again. Typing would get things moving. At another
> point, I tested pm-suspend on the netbook. Suspending worked, but
> awakening did not, so I had to power-cycle the machine. I use ext2 for
> reasons which I won't attempt to justify here, so when the machine
> came back up, it fsck'ed the root filesystem. Here again I saw things
> grind to a halt -- the progress meter stopped and the there was no
> disk activity. But if I moved my finger on the touchpad, things would
> get moving again. The only way to get the fsck to complete was to
> constantly be tickling the touchpad. I corresponded with Patrick
> Volkerding, telling him I suspected a scheduling problem and he
> informed me that the 13.1 kernel had tickless enabled, unlike 13. So I
> built a 2.6.33.3 kernel (from the Slackware-supplied kernel sources)
> with tickless disabled. With that kernel running, I power-cycled the
> machine to force a fsck of the root filesystem. This one proceeded to
> completion normally -- no external stimuli needed.
> 3. Tickless, scheduler
> 4. 2.6.33.3
> 7.1 ver_linux output attached
> 7.2 /proc/cpuinfo attached
> 7.3 /proc/modules attached
> 7.4 /proc/ioports, /proc/iomem attached
> 7.5 lspci attached
> 7.6 /proc/scsi/scsi attached

Can you post dmesg output from bootup?