milvus/internal/proxy/shardclient/channel_blacklist_test.go
wei liu 5f2e430941
enhance: Add channel-based node blacklist for LB policy retry (#46091)
issue: #46090
This change introduces a global node blacklist mechanism to immediately
cut off query traffic to failed delegators across all concurrent
requests.

Key features:
- Introduce ChannelBlacklist to track failed delegator nodes per channel
- When a query fails, the node is immediately blacklisted and excluded
from ALL subsequent requests (not just retries within the same request)
- Blacklisted nodes are automatically excluded during node selection
- Entries expire after configurable duration (default 30s) to allow
automatic recovery when nodes become healthy again
- Background cleanup loop removes expired entries periodically
- Add proxy.replicaBlacklistDuration and
proxy.replicaBlacklistCleanupInterval configuration parameters
- Blacklist can be disabled by setting duration to 0

Before this change:
- Failed nodes were only excluded within the same request's retry loop
- Concurrent requests would still attempt to query the failed node
- Each request had to experience its own failure before avoiding the
node

After this change:
- Once a node fails, it is immediately excluded from all requests
- New requests arriving during the blacklist period will skip the failed
node without experiencing any failure
- This significantly reduces latency spikes during node failures

Signed-off-by: Wei Liu <wei.liu@zilliz.com>
2026-01-06 11:01:29 +08:00

241 lines
7.5 KiB
Go

// Licensed to the LF AI & Data foundation under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package shardclient
import (
"testing"
"time"
"github.com/milvus-io/milvus/pkg/v2/util/paramtable"
)
func TestChannelBlacklist(t *testing.T) {
paramtable.Init()
t.Run("test add and get blacklisted nodes", func(t *testing.T) {
// Set blacklist duration to 1 second for testing
paramtable.Get().Save(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key, "1s")
defer paramtable.Get().Reset(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key)
blacklist := NewChannelBlacklist()
channel := "test_channel"
// Add nodes to blacklist
blacklist.Add(channel, 1)
blacklist.Add(channel, 2)
// Get blacklisted nodes
nodes := blacklist.GetBlacklistedNodes(channel)
if len(nodes) != 2 {
t.Errorf("expected 2 blacklisted nodes, got %d", len(nodes))
}
// Check that both nodes are in the list
nodeSet := make(map[int64]bool)
for _, n := range nodes {
nodeSet[n] = true
}
if !nodeSet[1] || !nodeSet[2] {
t.Errorf("expected nodes 1 and 2 to be blacklisted, got %v", nodes)
}
})
t.Run("test blacklist expiration", func(t *testing.T) {
// Set blacklist duration to 100ms for testing
paramtable.Get().Save(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key, "100ms")
defer paramtable.Get().Reset(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key)
blacklist := NewChannelBlacklist()
channel := "test_channel"
// Add node to blacklist
blacklist.Add(channel, 1)
// Node should be blacklisted
nodes := blacklist.GetBlacklistedNodes(channel)
if len(nodes) != 1 {
t.Errorf("expected 1 blacklisted node, got %d", len(nodes))
}
// Wait for expiration
time.Sleep(150 * time.Millisecond)
// Node should no longer be blacklisted
nodes = blacklist.GetBlacklistedNodes(channel)
if len(nodes) != 0 {
t.Errorf("expected 0 blacklisted nodes after expiration, got %d", len(nodes))
}
})
t.Run("test clear blacklist", func(t *testing.T) {
paramtable.Get().Save(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key, "1s")
defer paramtable.Get().Reset(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key)
blacklist := NewChannelBlacklist()
channel := "test_channel"
// Add nodes to blacklist
blacklist.Add(channel, 1)
blacklist.Add(channel, 2)
// Clear blacklist
blacklist.Clear(channel)
// Should have no blacklisted nodes
nodes := blacklist.GetBlacklistedNodes(channel)
if len(nodes) != 0 {
t.Errorf("expected 0 blacklisted nodes after clear, got %d", len(nodes))
}
})
t.Run("test blacklist disabled when duration is 0", func(t *testing.T) {
paramtable.Get().Save(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key, "0s")
defer paramtable.Get().Reset(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key)
blacklist := NewChannelBlacklist()
channel := "test_channel"
// Add node to blacklist - should be a no-op
blacklist.Add(channel, 1)
// Should have no blacklisted nodes
nodes := blacklist.GetBlacklistedNodes(channel)
if len(nodes) != 0 {
t.Errorf("expected 0 blacklisted nodes when disabled, got %d", len(nodes))
}
})
t.Run("test different channels have separate blacklists", func(t *testing.T) {
paramtable.Get().Save(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key, "1s")
defer paramtable.Get().Reset(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key)
blacklist := NewChannelBlacklist()
// Add different nodes to different channels
blacklist.Add("channel1", 1)
blacklist.Add("channel2", 2)
// Check channel1
nodes1 := blacklist.GetBlacklistedNodes("channel1")
if len(nodes1) != 1 || nodes1[0] != 1 {
t.Errorf("expected node 1 in channel1, got %v", nodes1)
}
// Check channel2
nodes2 := blacklist.GetBlacklistedNodes("channel2")
if len(nodes2) != 1 || nodes2[0] != 2 {
t.Errorf("expected node 2 in channel2, got %v", nodes2)
}
})
t.Run("test cleanup removes expired entries", func(t *testing.T) {
paramtable.Get().Save(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key, "50ms")
defer paramtable.Get().Reset(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key)
blacklist := NewChannelBlacklist()
channel := "test_channel"
// Add node to blacklist
blacklist.Add(channel, 1)
// Wait for expiration
time.Sleep(100 * time.Millisecond)
// Manually trigger cleanup
blacklist.cleanup()
// The internal map should be cleaned up
blacklist.mu.RLock()
_, exists := blacklist.blacklist[channel]
blacklist.mu.RUnlock()
if exists {
t.Errorf("expected channel to be removed from blacklist after cleanup")
}
})
t.Run("test start and close cleanup loop", func(t *testing.T) {
blacklist := NewChannelBlacklist()
blacklist.Start()
// Give some time for goroutine to start
time.Sleep(10 * time.Millisecond)
blacklist.Close()
// Should not panic or hang
})
t.Run("test get non-existent channel", func(t *testing.T) {
blacklist := NewChannelBlacklist()
// Get blacklisted nodes for a channel that was never added
nodes := blacklist.GetBlacklistedNodes("non_existent_channel")
if nodes != nil {
t.Errorf("expected nil for non-existent channel, got %v", nodes)
}
})
t.Run("test add same node updates expiration", func(t *testing.T) {
paramtable.Get().Save(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key, "200ms")
defer paramtable.Get().Reset(paramtable.Get().ProxyCfg.ReplicaBlacklistDuration.Key)
blacklist := NewChannelBlacklist()
channel := "test_channel"
// Add node to blacklist
blacklist.Add(channel, 1)
// Wait 100ms
time.Sleep(100 * time.Millisecond)
// Add same node again - should refresh expiration
blacklist.Add(channel, 1)
// Wait another 150ms (total 250ms from first add, but only 150ms from second add)
time.Sleep(150 * time.Millisecond)
// Node should still be blacklisted because expiration was refreshed
nodes := blacklist.GetBlacklistedNodes(channel)
if len(nodes) != 1 {
t.Errorf("expected 1 blacklisted node after refresh, got %d", len(nodes))
}
})
t.Run("test close can be called multiple times", func(t *testing.T) {
blacklist := NewChannelBlacklist()
blacklist.Start()
time.Sleep(10 * time.Millisecond)
// Close multiple times - should not panic due to closeOnce
blacklist.Close()
blacklist.Close()
blacklist.Close()
// Should not panic
})
t.Run("test cleanup loop with default interval", func(t *testing.T) {
// Set cleanup interval to 0 to trigger default value
paramtable.Get().Save(paramtable.Get().ProxyCfg.ReplicaBlacklistCleanupInterval.Key, "0s")
defer paramtable.Get().Reset(paramtable.Get().ProxyCfg.ReplicaBlacklistCleanupInterval.Key)
blacklist := NewChannelBlacklist()
blacklist.Start()
// Give some time for goroutine to start with default interval
time.Sleep(10 * time.Millisecond)
blacklist.Close()
// Should not panic or hang - default interval (10s) should be used
})
}