MySQL Bugs: #49668: ndb_config: Need more fine-grained restart impact description

Bug #49668	ndb_config: Need more fine-grained restart impact description
Submitted:	14 Dec 2009 13:30	Modified:	4 Jan 2010 10:40
Reporter:	Sivert Sørumgård	Email Updates:
Status:	Not a Bug	Impact on me:	None
Category:	MySQL Cluster: Cluster (NDB) storage engine	Severity:	S4 (Feature request)
Version:	mysql-5.1-telco-7.0	OS:	Any
Assigned to:		CPU Architecture:	Any

Description:
As of now, ndb_config --xml -- configinfo lists restart types as defined in the documentation (with some inconsistencies, as reported in another bug report; that's not the issue here). 

A rolling restart is not always required when a variable is changed. For some variables, it is enough to restart the only the node directly affected. For other variables, it may be enough to restart only nodes of a certain type. 

The output from ndb_config should include information describing these characteristics on a parseable format. The additional information could be provided by a new attribute in the param tag in the xml info. The information should tell which nodes should be restarted. Default may be to do a rolling restart of all nodes. A possible example may be, e.g. 

<param name="DataMemory" comment="Number bytes on each ndbd(DB) node allocated for storing data" type="unsigned" default="83886080" min="1048576" max="1099511627776" restartscope="ndb_mgmd,self"/>

The exact output format is TBD.

How to repeat:
Feature request

Suggested fix:
Extend output of ndb_config.

See also BUG#49781 and BUG#47366.

I'm closing this a !BUG. See the discussion in BUG#48432 for the reasons. 

(Summary: 'Happens to work' or 'appears to work' != guaranteed/supported behaviour.)

Sorry wrong bug # in previous comment -- see BUG#49781 for comments/discussion.

We are going directly for "online updatable parameters" so this step is not really necessary. When such a parameter is  avbailable it will be marked appropriately.