This is a common idiom in our current codebase:
couch_config:register(fun("couchdb", "os_process_timeout", NewTimeout) ->
It proves problematic for hot code upgrades. The issue is that the anonymous fun is held by the couch_config process but belongs to the module in which it is defined (here, couch_external_server.erl). If an expert user loads a new version of couch_external_server, the anonymous fun will belong to the 'old' version of the module. If she upgrades the module again, couch_config will be killed. That's no good.
The solution is to export the function that handles the configuration change or db update event. For instance
config_change("couchdb", "os_process_timeout", NewTimeout) ->
I have a patch for this that we've been using for some time in Cloudant, just need to clean it up and apply it to trunk.
|Status||Resolved [ 5 ]||Closed [ 6 ]|
|Skill Level||Regular Contributors Level (Easy to Medium) [ 10445 ]||Committers Level (Medium to Hard) [ 10446 ]|
|Status||Open [ 1 ]||Resolved [ 5 ]|
|Fix Version/s||2.0.0 [ 12315572 ]|
|Assignee||Adam Kocoloski [ kocolosk ]|
|Resolution||Fixed [ 1 ]|
|Fix Version/s||1.1 [ 12314933 ]|
|Field||Original Value||New Value|
|Skill Level||Regular Contributors Level (Easy to Medium)|