Find hotspots

Find the range or document that takes more load than its share, to change the key or the model.

Requirements

• Access to teseladb admin on a node of the cluster.
• A user with clusterMonitor.

Look at the leaders and the ranges

teseladb admin ranges --collection shop.orders

A range that splits again and again at its end, or a node that leads far more than the others, point to a key that always grows.

Look at the operations

db.currentOp({ ns: "shop.orders" });

Many operations in progress on the same _id point to a document everyone updates, such as a counter.

Check

After changing the key or creating the index with teselaBuckets, writes spread across several ranges.

Common problems

• The load does not drop when the range splits because the new end takes the same writes.

See also

• Keys and hotspots
• Find slow queries