The diagnostics dumped by the reader concurrency semaphore are pretty common-sight in logs, as soon as a node becomes problematic. The reason is that the reader concurrency semaphore acts as the canary in the coal mine: it is the first that starts screaming when the node or workload is unhealthy. This patch adds documentation of the content of the diagnostics and how to diagnose common problems based on it. Fixes: #10471 Closes #11970
Scylla developer documentation
This folder contains developer-oriented documentation concerning the ScyllaDB codebase. We also have a wiki, which contains additional developer-oriented documentation. There is currently no clear definition of what goes where, so when looking for something be sure to check both.
Seastar documentation can be found here.
User documentation can be found on docs.scylladb.com
For information on how to build Scylla and how to contribute visit HACKING.md and CONTRIBUTING.md.