ios - Firebase SDK, offline data storage with the option to sync at a later date -

when using firebase in ios app want give users option sync data firebase cloud or keep local. i've seen firebase has introduced option in sdk go offline , keep data syncing online i'm not sure intent of feature.

//keep data local. [firebase defaultconfig].persistenceenabled = yes; self.firebase = [[firebase alloc] initwithurl:kfirechatns]; [firebase gooffline]; 

from documentation seems gooffline(), , offline mode in general, build handle temporary periods device offline, , sync data in cloud device becomes online again. firebase offline mode capable of handling "permanent offline" scenario? or forcing firebase go "permanently offline" lead firebase accumulate more , more "meta data" never occurring future sync cloud? or discard old data @ point? or run out of offline cache disk space when max cache size reached ?

i got answer firebase support:

while can use gooffline() force client offline long time, performance deteriorate on time. firebase clients queue intermediate state changes, instead of updating stored state server does.