Answered Watch Dog

[jmac13]

Hi All,

(I'm using 10.2b)

Is watch dog worth having on? currently as default we don't have watch dog on our db's is this something that should be turned on?


Thanks

 

[Rob Fitzpatrick]

From the docs:

If you start multiple brokers, you should also run the Watchdog process (PROWDOG).
PROWDOG enables you to restart a dead secondary broker without shutting down the database
server.

The Watchdog cleans up after improperly terminated processes. For example, it releases any
locks or shared-memory structures that those processes might hold.

If the Watchdog finds a process that is no longer active, it releases all the appropriate
record locks, backs out any live transactions, releases any shared-memory locks, and
closes the connection. If the lost process is a server, it disconnects and cleans up all
appropriate remote clients.

If the process was changing shared memory when it terminated, shared memory is in an
inconsistent state; the Watchdog forces a shutdown to protect the database.

Why would you not want to protect the availability of your database and the integrity of your data, especially when it costs so little to do so?

 

[TomBascom]

In a word -- yes.

 

[jmac13]

Thanks all I'll switch this on.. not sure why it was decided why we wouldn't have this on

 

[jmac13]

Hi Guys,

sorry to be a pain but my boss wants proof that this process is doing what I say it does.. is there anyway to prove its doing the lovely stuff you say?

Thanks

 

[TomBascom]

You could always kill a few sessions and monitor the .lg file... (I'd do that on a test system -- real users get cranky when you kill their sessions just to show the boss what happens...)

Or maybe reading the documentation would satisfy him?

From page 523 of the Database Administration Manual (which can be found online at http://documentation.progress.com/output/OpenEdge112/pdfs/dmadm/dmadm.pdf ):

PROWDOG command
Starts the OpenEdge Watchdog process.
Parameters
db-name
Specifies the database to clean up after. The Watchdog cleans up after improperly terminated processes. For example, it releases any locks or shared-memory structures that those processes might hold.
Notes

If the Watchdog finds a process that is no longer active, it releases all the appropriate record locks, backs out any live transactions, releases any shared-memory locks, and closes the connection. If the lost process is a server, it disconnects and cleans up all appropriate remote clients.

If the process was changing shared memory when it terminated, shared memory is in an inconsistent state; the Watchdog forces a shutdown to protect thedatabase.

The Watchdog cannot detect lost remote clients because remote clients are not associated with a process. Instead,a network protocol timeout mechanism notifies the server that the network connection was lost.

 

[Rob Fitzpatrick]

Hi Guys,

sorry to be a pain but my boss wants proof that this process is doing what I say it does.. is there anyway to prove its doing the lovely stuff you say?

Thanks

Are you familiar with the Peter Principle?

 

[Cringer]

Is that where you deny all knowledge of something?

 

[TomBascom]

No, it's the one where you've risen to the point where you think you know it all (but it is obvious to others that you do not).

 

[jmac13]

Thanks guys.. the Peter Principle sounds about right for him..