It means that while inserts/updates/deletes are occurring, the processing necessary to add/modify that data in that index is causing blocking of other processes. That's all. Based on this, we don't know if you have a problem or not. Are your queries around this index and this table running slow? Are there user complaints? Are these indexes necessary to support SELECT statements? You need to answer these questions. Treat anything in your database like the Chesterton Fence. If you can at least understand why it's there, what it's doing, and whether it's doing what was intended, then you can easily decide to remove it or not.