Add guidance on managing kafka_internal/tx usage

Author: kbatuigas

modules/manage/pages/cluster-maintenance/disk-utilization.adoc

@@ -163,6 +163,24 @@ For periodic offset expiration, set the retention duration of consumer group off
 
 Redpanda supports group offset deletion with the Kafka OffsetDelete API through rpk with the xref:reference:rpk/rpk-group/rpk-group-offset-delete.adoc[`rpk group offset-delete`] command. The offset delete API provides finer control over culling consumer offsets. For example, it enables the manual removal of offsets that are tracked by Redpanda within the `__consumer_offsets` topic. The offsets requested to be removed will be removed only if either the group in question is in a dead state, or the partitions being deleted have no active subscriptions.
 
+== Manage transaction coordinator disk usage
+
+Redpanda uses the internal topic `kafka_internal/tx` to store transaction metadata for exactly-once and transactional producers. Over time, this topic can consume an excessive disk space in niche use cases that generate a large number of transactional sessions.
+
+You can manage the disk usage of `kafka_internal/tx` by tuning the following cluster properties:
+
+* config_ref:transaction_coordinator_delete_retention_ms,true,properties/cluster-properties[`transaction_coordinator_delete_retention_ms`]. Default: `604800000` (7 days).
+* config_ref:transactional_id_expiration_ms,true,properties/cluster-properties[`transactional_id_expiration_ms`]. Default: `604800000` (7 days).
+
+<<monitor-disk-space,Monitor disk usage>> of `kafka_internal/tx` using your storage metrics and decrease the values of these properties as needed to mitigate unbounded growth and manage storage consumption of the internal topic more effectively.
+
+To adjust these properties, run:
+
+[,bash]
+----
+rpk cluster config set transaction_coordinator_delete_retention_ms=<milliseconds> transactional_id_expiration_ms=<milliseconds>
+---- 
+
 == Configure segment size
 
 The `log_segment_size` property specifies the size of each log segment within the partition. Redpanda closes segments after they exceed this size and messages begin filling a new segment.