Picard limits requests to MusicBrainz to at most one per second. However, when Picard is configured to query a private mirror, it should be possible to lift the rate limit.

Original text of the ticket:

As discussed in previous threads on the forum (http://forums.musicbrainz.org/viewtopic.php?id=2302 , other multiple searches not included), users are looking to adjust and/or remove the 1 second query throttle implemented within Picard. The throttling for queries is a justifiable feature to prevent official servers from causing a horrible user experience between millions of users and queries, else crashing. However, the feature is more of a burden for those who've spent time to learn about MB vm and install their own private tagging server to support their private digital music collection. I believe it would be essential to provide a patch and/or option to either remove the limitation entirely, else an option for users to adjust the queries against their own private server. I'd agree that any attempt of flooding the MB official servers be dealt accordingly if in fact a user/s is abusing the feature within the software, however, there are ways to prevent this from occurring. There can be code implemented to block certain features designed for the official MB servers within the Picard tagging client when a user is attempting to modify the amount of search queries per second against their own private server, and/or require a user to create a user/pass or generate a token specific to their private server to allow the feature to function properly. This would also resolve issues with users receiving errors while looking up relationship/s Metadata.