That isn't the problem. I am entering numeric values, not '1m'.
I had already found Ivan's followup on this link and tried entering all of these values.
How to configure Openfire's caches | Ignite Realtime
cache.group.size = 5242880
cache.group.maxLifetime = 3600000
cache.username2roster.size = 5242880
cache.username2roster.maxLifetime = 3600000
cache.userGroup.size = 5242880
cache.userGroup.maxLifetime = 3600000
cache.userCache.size = 2097152
cache.userCache.maxLifetime = 3600000
cache.groupMeta.size = 2097152
cache.groupMeta.maxLifetime = 3600000
From what I can tell, cache.username2roster.size is the only cache size setting above that I've been able to modify successfully - have set it to 20242880, and the cache summary page say that the Roster cache is now 19.31M.
Trying to modify other values has not worked.
I can now also confirm that trying to modify last activity gives me the same type of message in warn.log:
2014.10.29 20:16:02 org.jivesoftware.util.cache.CacheFactory - Unable to parse cache.lastActivity.size using default value.
2014.10.29 20:16:02 org.jivesoftware.util.cache.CacheFactory - Unable to parse cache.userCache.size using default value.
My values for cache.userCache.size and cache.lastActivity.size are both 20242880.
Thanks,
D