Review request changed
Updated (March 27, 2011, 10:59 p.m.)
There are 2 major changes from the last patch: - added a parameter hive.metastore.batch.retrieve.max to control the maximum number of partitions can be retrieved from the metastore in one batch (default 300). In Hive.getPartitionsByNames(), the input partition name list are separated into sublists and call the metastore API for each sublist. - one of the most time consuming DB operations is the retrieve the sub-classes of MPartition. In particular the list of FieldSchema are retrieved for each partition and they are never used (the table's field schema is used for all partitions). So one of the changes here is to omit the retrieval of FieldSchema and make the table's fieldschema as the partitions. If later we need the partition's fieldschema for schema evaluation, we should add another function/flag for that. These changes reduce memory by 50% and CPU by 20%.
Posted (March 28, 2011, 10:34 a.m.)
mostly minor issues - can you update the patch, and I will try to get it in today