a3d73bfba7
Load balancer will recognize decommissioning nodes and will move tablet replicas away from such nodes with highest priority. Topology changes have now an extra step called "tablet draining" which calls the load balancer. The step will execute tablet migration track as long as there are nodes which require draining. It will not do regular load balancing. If load balancer is unable to find new tablet replicas, because RF cannot be met or availability is at risk due to insufficient node distribution in racks, it will throw an exception. Currently, topology change will retry in a loop. We should make this error cause topology change to be aborted. There is no infrastructure for aborts yet, so this is not implemented. Closes #15197 * github.com:scylladb/scylladb: tablets, raft topology: Add support for decommission with tablets tablet_allocator: Compute load sketch lazily tablet_allocator: Set node id correctly tablet_allocator: Make migration_plan a class tablets: Implement cleanup step storage_service, tablets: Prevent stale RPCs from running beyond their stage locator: Introduce tablet_metadata_guard locator, replica: Add a way to wait for table's effective_replication_map change storage_service, tablets: Extract do_tablet_operation() from stream_tablet() raft topology: Add break in the final case clause raft topology: Fix SIGSEGV when trace-level logging is enabled raft topology: Set node state in topology raft topology: Always set host id in topology
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.