# Software Architecture: `RegionRequestSender`

+ Locate keys & Send requests to peers
  + **_`1)`_** Get regions metadata from `PD/cache`
  + **_`2)`_** Locate & Group keys by `region`
  + **_`3)`_** Locate `region peer` address according to replica selector (e.g., `leader read`)
  + **_`4)`_** Send requests to `region peers` parallelly

![`smart`](TiKVClientRegionRequestSender_aa_001_20221027.png)

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Exponential backoff with equal jitter: `https://aws.amazon.com/blogs/architecture/exponential-backoff-and-jitter/`