feat(kv-router): plumb medium into worker-side placements (#7462)

Signed-off-by: PeaBrane <yanrpei@gmail.com>

lib/bench/kv_router/common/mod.rs

@@ -623,9 +623,9 @@ impl SequenceData {
 
     /// Convert to a store event.
     pub fn to_store_event(&self, event_id: u64) -> RouterEvent {
-        RouterEvent {
-            worker_id: self.worker_id,
-            event: KvCacheEvent {
+        RouterEvent::new(
+            self.worker_id,
+            KvCacheEvent {
                 event_id,
                 data: KvCacheEventData::Stored(KvCacheStoreData {
                     parent_hash: None,
@@ -642,21 +642,21 @@ impl SequenceData {
                 }),
                 dp_rank: 0,
             },
-        }
+        )
     }
 
     /// Convert to a remove event.
     pub fn to_remove_event(&self, event_id: u64) -> RouterEvent {
-        RouterEvent {
-            worker_id: self.worker_id,
-            event: KvCacheEvent {
+        RouterEvent::new(
+            self.worker_id,
+            KvCacheEvent {
                 event_id,
                 data: KvCacheEventData::Removed(KvCacheRemoveData {
                     block_hashes: self.external_hashes.clone(),
                 }),
                 dp_rank: 0,
             },
-        }
+        )
     }
 }
 

lib/bench/kv_router/mooncake_bench.rs

@@ -297,10 +297,7 @@ async fn run_benchmark(
                         }
                         WorkerTraceEntry::Event(event) => {
                             indexer
-                                .apply_event(RouterEvent {
-                                    worker_id: worker_id as u64,
-                                    event,
-                                })
+                                .apply_event(RouterEvent::new(worker_id as u64, event))
                                 .await;
                             Ok(None)
                         }

lib/kv-router/src/indexer/concurrent_radix_tree.rs

@@ -590,6 +590,7 @@ impl ConcurrentRadixTree {
                 // Create a store event for this worker
                 let event = RouterEvent {
                     worker_id: worker.worker_id,
+                    storage_tier: crate::protocols::StorageTier::Device,
                     event: KvCacheEvent {
                         event_id,
                         data: KvCacheEventData::Stored(KvCacheStoreData {

lib/kv-router/src/indexer/positional.rs

@@ -432,6 +432,7 @@ impl PositionalIndexer {
 
                 events.push(RouterEvent {
                     worker_id: worker.worker_id,
+                    storage_tier: crate::protocols::StorageTier::Device,
                     event: KvCacheEvent {
                         event_id,
                         data: KvCacheEventData::Stored(KvCacheStoreData {

lib/kv-router/src/indexer/radix_tree.rs

@@ -557,6 +557,7 @@ impl RadixTree {
                 // Create a store event for this worker
                 let event = RouterEvent {
                     worker_id: worker.worker_id,
+                    storage_tier: crate::protocols::StorageTier::Device,
                     event: KvCacheEvent {
                         event_id,
                         data: KvCacheEventData::Stored(KvCacheStoreData {

lib/kv-router/src/indexer/tests.rs

@@ -13,6 +13,7 @@ use super::concurrent_radix_tree::ConcurrentRadixTree;
 use super::positional::PositionalIndexer;
 use super::*;
 use crate::protocols::*;
+use crate::test_utils::{remove_event, router_event, stored_blocks_with_sequence_hashes};
 
 // ============================================================================
 // Helper functions
@@ -63,25 +64,15 @@ fn make_store_event_with_parent(
         local_hashes.iter().map(|&h| LocalBlockHash(h)).collect();
     let new_seq_hashes = &full_seq_hashes[prefix_hashes.len()..];
 
-    RouterEvent {
+    router_event(
         worker_id,
-        event: KvCacheEvent {
-            event_id: 0,
-            data: KvCacheEventData::Stored(KvCacheStoreData {
-                parent_hash,
-                blocks: new_block_hashes
-                    .iter()
-                    .zip(new_seq_hashes.iter())
-                    .map(|(&local, &seq)| KvCacheStoredBlockData {
-                        tokens_hash: local,
-                        block_hash: ExternalSequenceBlockHash(seq),
-                        mm_extra_info: None,
-                    })
-                    .collect(),
-            }),
-            dp_rank: 0,
-        },
-    }
+        0,
+        0,
+        KvCacheEventData::Stored(KvCacheStoreData {
+            parent_hash,
+            blocks: stored_blocks_with_sequence_hashes(&new_block_hashes, new_seq_hashes),
+        }),
+    )
 }
 
 /// Create a store event with all options.
@@ -95,25 +86,15 @@ fn make_store_event_full(
         local_hashes.iter().map(|&h| LocalBlockHash(h)).collect();
     let seq_hashes = compute_seq_hash_for_block(&local_block_hashes);
 
-    RouterEvent {
+    router_event(
         worker_id,
-        event: KvCacheEvent {
-            event_id: 0,
-            data: KvCacheEventData::Stored(KvCacheStoreData {
-                parent_hash,
-                blocks: local_block_hashes
-                    .iter()
-                    .zip(seq_hashes.iter())
-                    .map(|(&local, &seq)| KvCacheStoredBlockData {
-                        tokens_hash: local,
-                        block_hash: ExternalSequenceBlockHash(seq),
-                        mm_extra_info: None,
-                    })
-                    .collect(),
-            }),
-            dp_rank,
-        },
-    }
+        0,
+        dp_rank,
+        KvCacheEventData::Stored(KvCacheStoreData {
+            parent_hash,
+            blocks: stored_blocks_with_sequence_hashes(&local_block_hashes, &seq_hashes),
+        }),
+    )
 }
 
 /// Create a remove event for blocks with given local hashes.
@@ -131,19 +112,15 @@ fn make_remove_event_with_dp_rank(
         local_hashes.iter().map(|&h| LocalBlockHash(h)).collect();
     let seq_hashes = compute_seq_hash_for_block(&local_block_hashes);
 
-    RouterEvent {
+    remove_event(
         worker_id,
-        event: KvCacheEvent {
-            event_id: 0,
-            data: KvCacheEventData::Removed(KvCacheRemoveData {
-                block_hashes: seq_hashes
-                    .iter()
-                    .map(|&h| ExternalSequenceBlockHash(h))
-                    .collect(),
-            }),
-            dp_rank,
-        },
-    }
+        0,
+        dp_rank,
+        seq_hashes
+            .iter()
+            .map(|&h| ExternalSequenceBlockHash(h))
+            .collect(),
+    )
 }
 
 /// Create a remove event with parent hash for continuation sequences.
@@ -165,19 +142,15 @@ fn make_remove_event_with_parent(
 
     let suffix_seq_hashes = &full_seq_hashes[prefix_hashes.len()..];
 
-    RouterEvent {
+    remove_event(
         worker_id,
-        event: KvCacheEvent {
-            event_id: 0,
-            data: KvCacheEventData::Removed(KvCacheRemoveData {
-                block_hashes: suffix_seq_hashes
-                    .iter()
-                    .map(|&h| ExternalSequenceBlockHash(h))
-                    .collect(),
-            }),
-            dp_rank: 0,
-        },
-    }
+        0,
+        0,
+        suffix_seq_hashes
+            .iter()
+            .map(|&h| ExternalSequenceBlockHash(h))
+            .collect(),
+    )
 }
 
 /// Snapshot the tree state for deterministic comparison.
@@ -222,14 +195,7 @@ fn make_clear_event(worker_id: u64) -> RouterEvent {
 
 /// Create a clear event with a specific dp_rank.
 fn make_clear_event_with_dp_rank(worker_id: u64, dp_rank: u32) -> RouterEvent {
-    RouterEvent {
-        worker_id,
-        event: KvCacheEvent {
-            event_id: 0,
-            data: KvCacheEventData::Cleared,
-            dp_rank,
-        },
-    }
+    router_event(worker_id, 0, dp_rank, KvCacheEventData::Cleared)
 }
 
 // ============================================================================
@@ -646,16 +612,7 @@ async fn test_partial_block_removal(variant: &str) {
     let seq_hashes = compute_seq_hash_for_block(&full_hashes);
     let block_3_seq_hash = ExternalSequenceBlockHash(seq_hashes[2]); // Last block's hash
 
-    let remove_event = RouterEvent {
-        worker_id: 0,
-        event: KvCacheEvent {
-            event_id: 0,
-            data: KvCacheEventData::Removed(KvCacheRemoveData {
-                block_hashes: vec![block_3_seq_hash],
-            }),
-            dp_rank: 0,
-        },
-    };
+    let remove_event = remove_event(0, 0, 0, vec![block_3_seq_hash]);
     index.apply_event(remove_event).await;
 
     flush_and_settle(index.as_ref()).await;
@@ -698,16 +655,7 @@ async fn test_remove_mid_chain_block(variant: &str) {
     let seq_hashes = compute_seq_hash_for_block(&full_hashes);
     let block_3_seq_hash = ExternalSequenceBlockHash(seq_hashes[2]);
 
-    let remove_event = RouterEvent {
-        worker_id: 0,
-        event: KvCacheEvent {
-            event_id: 0,
-            data: KvCacheEventData::Removed(KvCacheRemoveData {
-                block_hashes: vec![block_3_seq_hash],
-            }),
-            dp_rank: 0,
-        },
-    };
+    let remove_event = remove_event(0, 0, 0, vec![block_3_seq_hash]);
     index.apply_event(remove_event).await;
 
     flush_and_settle(index.as_ref()).await;
@@ -895,47 +843,27 @@ async fn test_lora_and_base_model_blocks_do_not_conflict(variant: &str) {
     let lora_seq = compute_seq_hash_for_block(&lora_hashes);
 
     // Store base-model blocks on worker 0
-    let base_event = RouterEvent {
-        worker_id: 0,
-        event: KvCacheEvent {
-            event_id: 0,
-            data: KvCacheEventData::Stored(KvCacheStoreData {
-                parent_hash: None,
-                blocks: base_hashes
-                    .iter()
-                    .zip(base_seq.iter())
-                    .map(|(&local, &seq)| KvCacheStoredBlockData {
-                        tokens_hash: local,
-                        block_hash: ExternalSequenceBlockHash(seq),
-                        mm_extra_info: None,
-                    })
-                    .collect(),
-            }),
-            dp_rank: 0,
-        },
-    };
+    let base_event = router_event(
+        0,
+        0,
+        0,
+        KvCacheEventData::Stored(KvCacheStoreData {
+            parent_hash: None,
+            blocks: stored_blocks_with_sequence_hashes(&base_hashes, &base_seq),
+        }),
+    );
     index.apply_event(base_event).await;
 
     // Store LoRA blocks on worker 1
-    let lora_event = RouterEvent {
-        worker_id: 1,
-        event: KvCacheEvent {
-            event_id: 0,
-            data: KvCacheEventData::Stored(KvCacheStoreData {
-                parent_hash: None,
-                blocks: lora_hashes
-                    .iter()
-                    .zip(lora_seq.iter())
-                    .map(|(&local, &seq)| KvCacheStoredBlockData {
-                        tokens_hash: local,
-                        block_hash: ExternalSequenceBlockHash(seq),
-                        mm_extra_info: None,
-                    })
-                    .collect(),
-            }),
-            dp_rank: 0,
-        },
-    };
+    let lora_event = router_event(
+        1,
+        0,
+        0,
+        KvCacheEventData::Stored(KvCacheStoreData {
+            parent_hash: None,
+            blocks: stored_blocks_with_sequence_hashes(&lora_hashes, &lora_seq),
+        }),
+    );
     index.apply_event(lora_event).await;
 
     flush_and_settle(index.as_ref()).await;
@@ -1003,49 +931,29 @@ async fn test_lora_base_same_tokens_no_seq_hash_mismatch(variant: &str) {
 
     // Worker 0: base model
     index
-        .apply_event(RouterEvent {
-            worker_id: 0,
-            event: KvCacheEvent {
-                event_id: 0,
-                data: KvCacheEventData::Stored(KvCacheStoreData {
-                    parent_hash: None,
-                    blocks: base_local
-                        .iter()
-                        .zip(base_seq.iter())
-                        .map(|(&local, &seq)| KvCacheStoredBlockData {
-                            tokens_hash: local,
-                            block_hash: ExternalSequenceBlockHash(seq),
-                            mm_extra_info: None,
-                        })
-                        .collect(),
-                }),
-                dp_rank: 0,
-            },
-        })
+        .apply_event(router_event(
+            0,
+            0,
+            0,
+            KvCacheEventData::Stored(KvCacheStoreData {
+                parent_hash: None,
+                blocks: stored_blocks_with_sequence_hashes(&base_local, &base_seq),
+            }),
+        ))
         .await;
 
     // Worker 1: LoRA adapter — different LocalBlockHash, so this goes to
     // a separate tree path instead of colliding with worker 0's node.
     index
-        .apply_event(RouterEvent {
-            worker_id: 1,
-            event: KvCacheEvent {
-                event_id: 0,
-                data: KvCacheEventData::Stored(KvCacheStoreData {
-                    parent_hash: None,
-                    blocks: lora_local
-                        .iter()
-                        .zip(lora_seq.iter())
-                        .map(|(&local, &seq)| KvCacheStoredBlockData {
-                            tokens_hash: local,
-                            block_hash: ExternalSequenceBlockHash(seq),
-                            mm_extra_info: None,
-                        })
-                        .collect(),
-                }),
-                dp_rank: 0,
-            },
-        })
+        .apply_event(router_event(
+            1,
+            0,
+            0,
+            KvCacheEventData::Stored(KvCacheStoreData {
+                parent_hash: None,
+                blocks: stored_blocks_with_sequence_hashes(&lora_local, &lora_seq),
+            }),
+        ))
         .await;
 
     flush_and_settle(index.as_ref()).await;
@@ -1094,48 +1002,28 @@ async fn test_different_lora_adapters_do_not_conflict(variant: &str) {
 
     // Store adapter-a blocks on worker 0
     index
-        .apply_event(RouterEvent {
-            worker_id: 0,
-            event: KvCacheEvent {
-                event_id: 0,
-                data: KvCacheEventData::Stored(KvCacheStoreData {
-                    parent_hash: None,
-                    blocks: hashes_a
-                        .iter()
-                        .zip(seq_a.iter())
-                        .map(|(&local, &seq)| KvCacheStoredBlockData {
-                            tokens_hash: local,
-                            block_hash: ExternalSequenceBlockHash(seq),
-                            mm_extra_info: None,
-                        })
-                        .collect(),
-                }),
-                dp_rank: 0,
-            },
-        })
+        .apply_event(router_event(
+            0,
+            0,
+            0,
+            KvCacheEventData::Stored(KvCacheStoreData {
+                parent_hash: None,
+                blocks: stored_blocks_with_sequence_hashes(&hashes_a, &seq_a),
+            }),
+        ))
         .await;
 
     // Store adapter-b blocks on worker 1
     index
-        .apply_event(RouterEvent {
-            worker_id: 1,
-            event: KvCacheEvent {
-                event_id: 0,
-                data: KvCacheEventData::Stored(KvCacheStoreData {
-                    parent_hash: None,
-                    blocks: hashes_b
-                        .iter()
-                        .zip(seq_b.iter())
-                        .map(|(&local, &seq)| KvCacheStoredBlockData {
-                            tokens_hash: local,
-                            block_hash: ExternalSequenceBlockHash(seq),
-                            mm_extra_info: None,
-                        })
-                        .collect(),
-                }),
-                dp_rank: 0,
-            },
-        })
+        .apply_event(router_event(
+            1,
+            0,
+            0,
+            KvCacheEventData::Stored(KvCacheStoreData {
+                parent_hash: None,
+                blocks: stored_blocks_with_sequence_hashes(&hashes_b, &seq_b),
+            }),
+        ))
         .await;
 
     flush_and_settle(index.as_ref()).await;
@@ -1317,16 +1205,7 @@ async fn test_long_sequence_partial_removal(variant: &str) {
         .map(|&h| ExternalSequenceBlockHash(h))
         .collect();
 
-    let remove_event = RouterEvent {
-        worker_id: 0,
-        event: KvCacheEvent {
-            event_id: 0,
-            data: KvCacheEventData::Removed(KvCacheRemoveData {
-                block_hashes: remove_hashes,
-            }),
-            dp_rank: 0,
-        },
-    };
+    let remove_event = remove_event(0, 0, 0, remove_hashes);
     index.apply_event(remove_event).await;
 
     flush_and_settle(index.as_ref()).await;
@@ -1868,6 +1747,7 @@ async fn test_frequency(variant: &str) {
 // KvIndexerMetrics tests
 // ============================================================================
 
+#[cfg(feature = "metrics")]
 #[test]
 fn test_increment_event_applied() {
     let metrics = KvIndexerMetrics::new_unregistered();

lib/kv-router/src/protocols.rs

@@ -133,6 +133,94 @@ impl WorkerWithDpRank {
     }
 }
 
+#[derive(Debug, Clone, Copy, Default, Serialize, Deserialize, PartialEq, Eq, Hash)]
+#[serde(rename_all = "snake_case")]
+pub enum StorageTier {
+    #[default]
+    Device,
+    HostPinned,
+    Disk,
+    External,
+}
+
+impl StorageTier {
+    pub fn from_kv_medium(medium: &str) -> Option<Self> {
+        match medium {
+            "GPU" | "DEVICE" => Some(Self::Device),
+            "CPU_PINNED" | "CPU_TIER1" => Some(Self::HostPinned),
+            "CPU_TIER2" | "DISK" | "NVME" => Some(Self::Disk),
+            "EXTERNAL" | "NETWORK" | "REMOTE" | "SHARED" => Some(Self::External),
+            _ => None,
+        }
+    }
+
+    pub fn from_kv_medium_or_default(medium: Option<&str>) -> Self {
+        medium
+            .and_then(Self::from_kv_medium)
+            .unwrap_or(Self::Device)
+    }
+
+    pub fn is_gpu(self) -> bool {
+        matches!(self, Self::Device)
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Hash)]
+pub enum PlacementOwner {
+    LocalWorker(WorkerWithDpRank),
+    Shared,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Hash)]
+pub struct Placement {
+    pub owner: PlacementOwner,
+    pub tier: StorageTier,
+}
+
+impl Placement {
+    pub fn local_worker(worker_id: WorkerId, dp_rank: DpRank, tier: StorageTier) -> Self {
+        Self {
+            owner: PlacementOwner::LocalWorker(WorkerWithDpRank::new(worker_id, dp_rank)),
+            tier,
+        }
+    }
+
+    pub fn local_gpu(worker_id: WorkerId, dp_rank: DpRank) -> Self {
+        Self::local_worker(worker_id, dp_rank, StorageTier::Device)
+    }
+
+    pub fn is_local_gpu(&self) -> bool {
+        matches!(self.owner, PlacementOwner::LocalWorker(_)) && self.tier.is_gpu()
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
+pub struct PlacementEvent {
+    pub placement: Placement,
+    pub event: KvCacheEvent,
+}
+
+impl PlacementEvent {
+    pub fn new(placement: Placement, event: KvCacheEvent) -> Self {
+        Self { placement, event }
+    }
+
+    pub fn local_gpu(worker_id: WorkerId, event: KvCacheEvent) -> Self {
+        Self::new(Placement::local_gpu(worker_id, event.dp_rank), event)
+    }
+
+    pub fn into_router_event(self) -> Option<RouterEvent> {
+        let PlacementOwner::LocalWorker(worker) = self.placement.owner else {
+            return None;
+        };
+        Some(RouterEvent::with_storage_tier(
+            worker.worker_id,
+            self.event,
+            self.placement.tier,
+        ))
+    }
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize)]
 #[serde(tag = "method", rename_all = "snake_case")]
 pub enum RouterRequest {
@@ -512,6 +600,9 @@ pub enum KvCacheEventError {
 pub struct RouterEvent {
     /// The ID of the worker emitting the event.
     pub worker_id: WorkerId,
+    /// The storage tier associated with the event.
+    #[serde(default)]
+    pub storage_tier: StorageTier,
     /// The cache event associated with the worker.
     pub event: KvCacheEvent,
 }
@@ -528,7 +619,19 @@ impl RouterEvent {
     ///
     /// A new `RouterEvent`.
     pub fn new(worker_id: WorkerId, event: KvCacheEvent) -> Self {
-        Self { worker_id, event }
+        Self::with_storage_tier(worker_id, event, StorageTier::Device)
+    }
+
+    pub fn with_storage_tier(
+        worker_id: WorkerId,
+        event: KvCacheEvent,
+        storage_tier: StorageTier,
+    ) -> Self {
+        Self {
+            worker_id,
+            storage_tier,
+            event,
+        }
     }
 }
 

lib/kv-router/src/standalone_indexer/listener.rs

@@ -11,7 +11,7 @@ use tokio::sync::watch;
 use tokio_util::sync::CancellationToken;
 use zeromq::{DealerSocket, Socket, SocketRecv, SocketSend, SubSocket};
 
-use crate::protocols::{RouterEvent, WorkerId};
+use crate::protocols::{RouterEvent, WorkerId, WorkerWithDpRank};
 use crate::zmq_wire::{KvEventBatch, convert_event};
 
 use super::indexer::Indexer;
@@ -111,9 +111,19 @@ async fn replay_gap(
             .data_parallel_rank
             .map_or(dp_rank, |rank| rank.cast_unsigned());
         for raw_event in batch.events {
-            let kv_event =
-                convert_event(raw_event, seq, block_size, effective_dp_rank, warning_count);
-            let router_event = RouterEvent::new(worker_id, kv_event);
+            let placement_event = convert_event(
+                raw_event,
+                seq,
+                block_size,
+                WorkerWithDpRank::new(worker_id, effective_dp_rank),
+                warning_count,
+            );
+            if !placement_event.placement.is_local_gpu() {
+                continue;
+            }
+            let router_event = placement_event
+                .into_router_event()
+                .expect("local worker placement must convert to router event");
             indexer.apply_event(router_event).await;
         }
         watermark.store(seq, Ordering::Release);
@@ -381,9 +391,19 @@ async fn zmq_recv_loop(
                     .data_parallel_rank
                     .map_or(dp_rank, |rank| rank.cast_unsigned());
                 for raw_event in batch.events {
-                    let kv_event =
-                        convert_event(raw_event, seq, block_size, effective_dp_rank, &warning_count);
-                    let router_event = RouterEvent::new(worker_id, kv_event);
+                    let placement_event = convert_event(
+                        raw_event,
+                        seq,
+                        block_size,
+                        WorkerWithDpRank::new(worker_id, effective_dp_rank),
+                        &warning_count,
+                    );
+                    if !placement_event.placement.is_local_gpu() {
+                        continue;
+                    }
+                    let router_event = placement_event
+                        .into_router_event()
+                        .expect("local worker placement must convert to router event");
                     indexer.apply_event(router_event).await;
                     messages_processed += 1;
                 }

lib/kv-router/src/test_utils.rs

@@ -12,6 +12,51 @@ use crate::protocols::{
 };
 use crate::sequences::SequencePublisher;
 
+pub fn router_event(
+    worker_id: WorkerId,
+    event_id: u64,
+    dp_rank: u32,
+    data: KvCacheEventData,
+) -> RouterEvent {
+    RouterEvent::new(
+        worker_id,
+        KvCacheEvent {
+            event_id,
+            data,
+            dp_rank,
+        },
+    )
+}
+
+pub fn stored_blocks_with_sequence_hashes(
+    local_hashes: &[LocalBlockHash],
+    seq_hashes: &[u64],
+) -> Vec<KvCacheStoredBlockData> {
+    local_hashes
+        .iter()
+        .zip(seq_hashes.iter())
+        .map(|(&local, &seq)| KvCacheStoredBlockData {
+            tokens_hash: local,
+            block_hash: ExternalSequenceBlockHash(seq),
+            mm_extra_info: None,
+        })
+        .collect()
+}
+
+pub fn remove_event(
+    worker_id: WorkerId,
+    event_id: u64,
+    dp_rank: u32,
+    block_hashes: Vec<ExternalSequenceBlockHash>,
+) -> RouterEvent {
+    router_event(
+        worker_id,
+        event_id,
+        dp_rank,
+        KvCacheEventData::Removed(KvCacheRemoveData { block_hashes }),
+    )
+}
+
 /// Creates blocks with artificial hash mapping (hash * 100) for testing.
 pub fn make_blocks(hashes: Vec<u64>) -> Vec<KvCacheStoredBlockData> {
     hashes
@@ -40,30 +85,19 @@ pub fn create_store_event(
     hashes: Vec<u64>,
     parent: Option<ExternalSequenceBlockHash>,
 ) -> RouterEvent {
-    RouterEvent {
-        worker_id,
-        event: KvCacheEvent {
-            event_id,
-            data: add_blocks(hashes, parent),
-            dp_rank: 0,
-        },
-    }
+    router_event(worker_id, event_id, 0, add_blocks(hashes, parent))
 }
 
 pub fn create_remove_event(worker_id: WorkerId, event_id: u64, hashes: Vec<u64>) -> RouterEvent {
-    RouterEvent {
+    remove_event(
         worker_id,
-        event: KvCacheEvent {
-            event_id,
-            data: KvCacheEventData::Removed(KvCacheRemoveData {
-                block_hashes: hashes
-                    .iter()
-                    .map(|i| ExternalSequenceBlockHash(*i * 100))
-                    .collect(),
-            }),
-            dp_rank: 0,
-        },
-    }
+        event_id,
+        0,
+        hashes
+            .iter()
+            .map(|i| ExternalSequenceBlockHash(*i * 100))
+            .collect(),
+    )
 }
 
 /// No-op [`SequencePublisher`] for tests and benchmarks that don't need event transport.

lib/kv-router/src/zmq_wire.rs

@@ -18,7 +18,8 @@ use serde::de::{self, Deserializer, IgnoredAny, MapAccess, SeqAccess, Visitor};
 
 use crate::protocols::{
     BlockExtraInfo, BlockMmObjectInfo, ExternalSequenceBlockHash, KvCacheEvent, KvCacheEventData,
-    KvCacheRemoveData, KvCacheStoreData, KvCacheStoredBlockData, compute_block_hash_for_seq,
+    KvCacheRemoveData, KvCacheStoreData, KvCacheStoredBlockData, Placement, PlacementEvent,
+    StorageTier, WorkerWithDpRank, compute_block_hash_for_seq,
 };
 
 // -------------------------------------------------------------------------
@@ -335,16 +336,22 @@ impl<'de> Visitor<'de> for RawKvEventVisitor {
 // Event conversion --------------------------------------------------------
 // -------------------------------------------------------------------------
 
-/// Convert a raw event coming from the ZMQ channel into the internal
-/// [`KvCacheEvent`] representation used by the router.
+/// Convert a raw event coming from the ZMQ channel into a placement-aware worker event.
 pub fn convert_event(
     raw: RawKvEvent,
     event_id: u64,
     kv_block_size: u32,
-    dp_rank: u32,
+    worker: WorkerWithDpRank,
     warning_count: &Arc<AtomicU32>,
-) -> KvCacheEvent {
-    match raw {
+) -> PlacementEvent {
+    let storage_tier = match &raw {
+        RawKvEvent::BlockStored { medium, .. } | RawKvEvent::BlockRemoved { medium, .. } => {
+            StorageTier::from_kv_medium_or_default(medium.as_deref())
+        }
+        RawKvEvent::AllBlocksCleared => StorageTier::Device,
+    };
+    let dp_rank = worker.dp_rank;
+    let event = match raw {
         RawKvEvent::BlockStored {
             block_hashes,
             parent_block_hash,
@@ -369,13 +376,16 @@ pub fn convert_event(
                     // Return an empty Removed instead of Cleared to avoid nuking
                     // the worker's entire index state. An empty Removed is a no-op
                     // in the radix tree (zero iterations, returns Ok(())).
-                    return KvCacheEvent {
-                        event_id,
-                        data: KvCacheEventData::Removed(KvCacheRemoveData {
-                            block_hashes: vec![],
-                        }),
-                        dp_rank,
-                    };
+                    return PlacementEvent::new(
+                        Placement::local_worker(worker.worker_id, worker.dp_rank, storage_tier),
+                        KvCacheEvent {
+                            event_id,
+                            data: KvCacheEventData::Removed(KvCacheRemoveData {
+                                block_hashes: vec![],
+                            }),
+                            dp_rank,
+                        },
+                    );
                 }
             }
 
@@ -422,7 +432,12 @@ pub fn convert_event(
             data: KvCacheEventData::Cleared,
             dp_rank,
         },
-    }
+    };
+
+    PlacementEvent::new(
+        Placement::local_worker(worker.worker_id, worker.dp_rank, storage_tier),
+        event,
+    )
 }
 
 pub fn create_stored_block_from_parts(

lib/llm/src/block_manager/kv_consolidator/tracker.rs

@@ -17,7 +17,7 @@
 
 use std::collections::{HashMap, HashSet};
 
-use dynamo_kv_router::protocols::XXH3_SEED;
+use dynamo_kv_router::protocols::{StorageTier as RouterStorageTier, XXH3_SEED};
 
 /// LocalBlockHash type (content hash from tokens only)
 type LocalBlockHash = u64;
@@ -108,12 +108,7 @@ pub enum StorageTier {
 impl StorageTier {
     /// Parse from vLLM's medium string (e.g., "GPU", "CPU_TIER1", "CPU_TIER2")
     pub fn from_vllm_medium(s: &str) -> Option<Self> {
-        match s {
-            "GPU" => Some(StorageTier::Device),
-            "CPU_TIER1" => Some(StorageTier::HostPinned),
-            "CPU_TIER2" => Some(StorageTier::Disk),
-            _ => None,
-        }
+        RouterStorageTier::from_kv_medium(s).map(Into::into)
     }
 
     /// Convert to vLLM's medium string
@@ -135,6 +130,16 @@ impl StorageTier {
     }
 }
 
+impl From<RouterStorageTier> for StorageTier {
+    fn from(value: RouterStorageTier) -> Self {
+        match value {
+            RouterStorageTier::Device => Self::Device,
+            RouterStorageTier::HostPinned => Self::HostPinned,
+            RouterStorageTier::Disk | RouterStorageTier::External => Self::Disk,
+        }
+    }
+}
+
 /// Legacy type alias for backward compatibility
 #[deprecated(note = "Use StorageTier instead")]
 pub type StorageMedium = StorageTier;