[c-nsp] no scheduler max-sched-time

[Jared Mauch]

	The problem clearly is inconsisent behaviour exhibited
by Cisco on this front.  The need to "nvgen" what really is enabled
is key here.  There's no way to disable some services that
are enabled on the routers, and sometimes you don't realize something
is there until you disable it.  Take for example the recent DHCP and H.323
advisories.

	If it doesn't nvgen, people don't know it's there.

	Plus there's all sorts of other random junk that nvgens
as well.

	Taking a clean 12.2(25)S1 boot (after write erase), you get all
sorts of junk about "call rsvp-sync" and a bunch of mpls commands
that don't exactly negate "properly", imho.

	If you have not enabled mpls, or "tag switching", why is my
router generate this extra junk?

	/sigh

	- jared

On Mon, Nov 29, 2004 at 12:47:10PM -0800, Bruce Pinsky wrote:
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> Jeff Chambers wrote:
> | I noticed the following command configured on a Cisco
> | 7206VXR router that was recently upgraded to 12.2(25)S1.
> |
> | "no scheduler max-sched-time"
> |
> |
> | The CLI gives me the following help information.
> |
> | Router(config)#scheduler ?
> |   max-sched-time    Maximum time scheduler can run without flagging an 
> error
> |
> 
> There is no formal public documentation that I can find.  However, this
> command comes from the introduction of a new CPU HOG (scheduler watchdog)
> reporting mechanism that was introduced into 12.2S (as well as 12.0S and
> 12.2T).  Prior to this new mechanism, CPU HOG's were only reported after a
> process would suspend. This is less useful because it does not indicate
> where most of the time is being spent to cause the CPU HOG. With the
> introduction of the enhancement, a CPU HOG is reported at the moment it
> crosses the defined threshold.  The command is used to changed the default
> maximum threshold.  Setting the maximum to zero or using the explicit "no"
> version of the command disables the capability.
> 
> |
> | This command only shows up in the configuration if
> | "service internal" is configured.  I can't find any
> | documentation for the "no scheduler max-sched-time"
> | command.  Can anyone point me in the right direction?
> |
> | I'm mainly curious if this command is harmless or not.
> | After reading bug ID CSCdw61805, it appears leaving
> | "service internal" configured on a production router
> | might be a bad idea by itself.
> |
> 
> "service internal" does expose a number of commands that can have negative
> effects on system operation if used improperly.  This is usually the
> motivation for obscuring them with this mode of the parser.  The fact that
> most are undocumented is unfortunate because it leaves people to guess at
> both what the command does and how detrimental it may or may not be.  There
> is a push inside of cisco to eliminate and prevent undocumented commands
> going forward, but I can't say when or if the old ones might get done.
> 
> - --
> =========
> bep
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-- 
Jared Mauch  | pgp key available via finger from jared at puck.nether.net
clue++;      | http://puck.nether.net/~jared/  My statements are only mine.