This page shows you how to resolve issues with Firestore in Datastore mode.
Latency
The table below describes possible causes of increased latency:
| Latency cause | Types of operations affected | Resolution |
|---|---|---|
| Sustained traffic exceeding the 500-50-5 rule. | read, write |
For rapid traffic increases, Datastore mode attempts to automatically scale to meet the increased demand. When Datastore mode scales, latency begins to decrease. Hot-spots (high read, write, and delete rates to a narrow entity range) limit the ability of Datastore mode to scale. Review designing for scale and identify hot-spots in your application. |
| Contention, either from updating a single entity too frequently or from transactions. | read, write |
Reduce the write rate to individual entities. Review transaction isolation and consistency and how you use transactions. |
| Slow merge-join queries. | read |
For example, queries with multiple equality filters (==)
but not backed by composite indexes can result in slow merge-join queries.
To improve performance, add composite indexes for these queries,
see
Optimizing indexes.
|
| Large reads that return many entities. | read | Use query cursors to split large reads. |