[indiana-discuss] System freeze in snv_106

[Chris Ridd]

On 5 Feb 2009, at 14:44, Brian Ruthven - Sun UK wrote:

>
> Hi Chris,
>
> If you are talking about the delay before the clock thread declaring  
> the system has hung, then yes, this is tunable. The variable is  
> snoop_interval and the units are expressed as microseconds. Default  
> value is 50000000 (50 seconds). See http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/uts/common/conf/param.c 
>  for the definition of SNOOP_INTERVAL_DEFAULT and snoop_interval.
>
> For example, put the following line in /etc/system and reboot:
>
>     set snooping=1
>     set snoop_interval = 10000000

This is exactly what I was looking for, thanks.

> This will set the deadman timer to 10 seconds and enable the deadman  
> checking code in clock.c. I would not advise setting either variable  
> on a live system using mdb.

OK, I'll try not to.

> The value is a balance between getting the system back quickly vs.  
> accidentally tripping the system for a period of inactivity due to  
> hardware intervention (e.g. repeated correction of a system bus  
> event by the hardware). You can set it to whatever you want (minimum  
> value is 1 second) for debugging purposes, but watch out for some  
> false hits if you are too aggressive with the setting.
>
> Also bear in mind that with a large system which takes 15 minutes to  
> reboot anyway, 50 seconds is not a lot :-)

This is a small box, but I think I can see what sort of problem this  
could cause ;-)

Cheers,

Chris