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@ -1513,6 +1513,501 @@ graph LR
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style GLOBAL fill:#fff3e0
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```
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|
|
|
## Galera Cluster Monitoring
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|
|
### WSREP Variable Monitoring Flow
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|
|
```mermaid
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|
|
graph TB
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|
|
subgraph "Galera Health Check Pipeline"
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|
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START[Monitor Timer Trigger] --> CHECK_INTERVAL{Interval Elapsed?}
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|
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CHECK_INTERVAL -->|Yes| FETCH_WSREP[Fetch WSREP Variables]
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CHECK_INTERVAL -->|No| WAIT[Wait]
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|
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FETCH_WSREP --> PARSE[Parse WSREP Status]
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subgraph "WSREP Variables Check"
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PARSE --> V1[wsrep_ready]
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PARSE --> V2[wsrep_cluster_status]
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PARSE --> V3[wsrep_local_state]
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PARSE --> V4[wsrep_desync]
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PARSE --> V5[wsrep_reject_queries]
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PARSE --> V6[wsrep_sst_donor_rejects_queries]
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end
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V1 --> EVAL{Evaluate Health}
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V2 --> EVAL
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V3 --> EVAL
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V4 --> EVAL
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V5 --> EVAL
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V6 --> EVAL
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EVAL --> DECISION{Healthy?}
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DECISION -->|Yes| MARK_ONLINE[Mark Server ONLINE]
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DECISION -->|No| CHECK_TIMEOUT{Timeout Count}
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CHECK_TIMEOUT -->|< Max| INCREMENT[Increment Counter]
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CHECK_TIMEOUT -->|>= Max| MARK_OFFLINE[Mark Server OFFLINE]
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INCREMENT --> LOG_WARNING[Log Warning]
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MARK_ONLINE --> UPDATE_HG[Update Hostgroup]
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MARK_OFFLINE --> UPDATE_HG
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LOG_WARNING --> UPDATE_HG
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|
|
end
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|
style START fill:#e1f5fe
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style FETCH_WSREP fill:#fff3e0
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style MARK_ONLINE fill:#c8e6c9
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style MARK_OFFLINE fill:#ffebee
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```
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|
|
|
|
### Galera Node State Transitions
|
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|
|
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|
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|
|
|
```mermaid
|
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|
|
stateDiagram-v2
|
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|
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[*] --> Disconnected: Initial
|
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Disconnected --> Connecting: Join Cluster
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Connecting --> Joining: SST/IST
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Joining --> Synced: State Transfer Complete
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Synced --> Donor: Become Donor
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Donor --> Synced: Donation Complete
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Synced --> Desync: Manual Desync
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Desync --> Synced: Resync
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|
|
state "wsrep_local_state" {
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|
|
1_Joining: 1 - Joining
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|
|
2_Donor: 2 - Donor/Desynced
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|
3_Joined: 3 - Joined
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|
4_Synced: 4 - Synced
|
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|
|
}
|
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|
|
state "wsrep_cluster_status" {
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|
|
Primary: Primary Component
|
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|
NonPrimary: Non-Primary
|
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|
|
Disconnected_State: Disconnected
|
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|
|
}
|
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Synced --> Primary: Normal Operation
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Primary --> NonPrimary: Network Partition
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NonPrimary --> Primary: Partition Healed
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Synced --> Error: wsrep_reject_queries=ON
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Error --> Synced: Recovery
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|
|
note right of Donor
|
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|
|
|
During SST donation:
|
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|
|
|
- wsrep_sst_donor_rejects_queries
|
|
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|
|
- Affects availability
|
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|
|
end note
|
|
|
|
|
```
|
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|
|
|
|
|
|
|
|
## Bootstrap Mode Implementation
|
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|
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|
|
|
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|
|
### Group Replication Bootstrap Flow
|
|
|
|
|
|
|
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|
|
```mermaid
|
|
|
|
|
graph TB
|
|
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|
|
subgraph "Bootstrap Initialization"
|
|
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|
|
DETECT[Detect Bootstrap Mode] --> CHECK_VAR{bootstrap_variables?}
|
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|
|
CHECK_VAR -->|Present| PARSE_JSON[Parse JSON Config]
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|
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CHECK_VAR -->|Absent| NORMAL_START[Normal Startup]
|
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|
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PARSE_JSON --> EXTRACT[Extract Parameters]
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|
|
EXTRACT --> VAL_HG[writer_hostgroup]
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|
|
EXTRACT --> VAL_RD[reader_hostgroup]
|
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|
|
EXTRACT --> VAL_WR[writer_is_also_reader]
|
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|
|
EXTRACT --> VAL_MX[max_writers]
|
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|
|
end
|
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|
|
subgraph "Auto-Discovery Phase"
|
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|
|
VAL_MX --> QUERY_NODES[Query All Nodes]
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|
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QUERY_NODES --> CHECK_PRIMARY{Find Primary?}
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CHECK_PRIMARY -->|Found| GET_MEMBERS[Get Member List]
|
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|
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CHECK_PRIMARY -->|Not Found| RETRY{Retry Count?}
|
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|
|
RETRY -->|< Max| WAIT_RETRY[Wait & Retry]
|
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|
|
RETRY -->|>= Max| FAIL[Bootstrap Failed]
|
|
|
|
|
|
|
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|
|
WAIT_RETRY --> QUERY_NODES
|
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|
|
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|
|
GET_MEMBERS --> BUILD_CONFIG[Build Configuration]
|
|
|
|
|
end
|
|
|
|
|
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|
|
|
|
subgraph "Configuration Generation"
|
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|
|
|
BUILD_CONFIG --> GEN_SERVERS[Generate mysql_servers]
|
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|
|
BUILD_CONFIG --> GEN_GROUPS[Generate mysql_group_replication_hostgroups]
|
|
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|
|
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|
|
|
GEN_SERVERS --> POPULATE_WR[Populate Writer HG]
|
|
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|
|
GEN_SERVERS --> POPULATE_RD[Populate Reader HG]
|
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|
|
|
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|
|
|
|
subgraph "Server Assignment"
|
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|
|
|
POPULATE_WR --> PRIMARY_NODE[Primary → Writer HG]
|
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|
|
POPULATE_RD --> SECONDARY_NODES[Secondaries → Reader HG]
|
|
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|
|
|
|
|
|
|
VAL_WR -->|writer_is_also_reader=1| PRIMARY_BOTH[Primary → Both HGs]
|
|
|
|
|
end
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
subgraph "Activation"
|
|
|
|
|
PRIMARY_NODE --> LOAD_RUNTIME[Load to Runtime]
|
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|
|
|
SECONDARY_NODES --> LOAD_RUNTIME
|
|
|
|
|
PRIMARY_BOTH --> LOAD_RUNTIME
|
|
|
|
|
|
|
|
|
|
LOAD_RUNTIME --> SAVE_DISK[Save to Disk]
|
|
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|
|
SAVE_DISK --> MONITOR_START[Start Monitoring]
|
|
|
|
|
MONITOR_START --> COMPLETE[Bootstrap Complete]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
style DETECT fill:#e1f5fe
|
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|
|
|
style CHECK_PRIMARY fill:#fff3e0
|
|
|
|
|
style COMPLETE fill:#c8e6c9
|
|
|
|
|
style FAIL fill:#ffebee
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
### Bootstrap Variables Processing
|
|
|
|
|
|
|
|
|
|
```mermaid
|
|
|
|
|
graph LR
|
|
|
|
|
subgraph "JSON Bootstrap Config"
|
|
|
|
|
JSON[bootstrap_variables JSON] --> PARSE{Parse JSON}
|
|
|
|
|
|
|
|
|
|
PARSE --> P1[writer_hostgroup: 10]
|
|
|
|
|
PARSE --> P2[reader_hostgroup: 11]
|
|
|
|
|
PARSE --> P3[backup_writer_hostgroup: 12]
|
|
|
|
|
PARSE --> P4[offline_hostgroup: 9999]
|
|
|
|
|
PARSE --> P5[max_writers: 1]
|
|
|
|
|
PARSE --> P6[writer_is_also_reader: 2]
|
|
|
|
|
PARSE --> P7[max_transactions_behind: 0]
|
|
|
|
|
|
|
|
|
|
subgraph "writer_is_also_reader modes"
|
|
|
|
|
P6 --> M0[0: Writer not in reader HG]
|
|
|
|
|
P6 --> M1[1: Writer also in reader HG]
|
|
|
|
|
P6 --> M2[2: Writer in backup_writer + reader HG]
|
|
|
|
|
end
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
style JSON fill:#e1f5fe
|
|
|
|
|
style M2 fill:#c8e6c9
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
## Query Digest Generation Pipeline
|
|
|
|
|
|
|
|
|
|
### SpookyV2 Hash Calculation
|
|
|
|
|
|
|
|
|
|
```mermaid
|
|
|
|
|
graph TB
|
|
|
|
|
subgraph "Query Normalization Pipeline"
|
|
|
|
|
QUERY[Original Query] --> SIZE_CHECK{Size > 100KB?}
|
|
|
|
|
|
|
|
|
|
SIZE_CHECK -->|Yes| LARGE_QUERY[Large Query Path]
|
|
|
|
|
SIZE_CHECK -->|No| NORMAL_PATH[Normal Path]
|
|
|
|
|
|
|
|
|
|
subgraph "Tokenization Process"
|
|
|
|
|
NORMAL_PATH --> TOKENIZE[Tokenize SQL]
|
|
|
|
|
TOKENIZE --> REPLACE_LITERALS[Replace Literals with ?]
|
|
|
|
|
REPLACE_LITERALS --> NORMALIZE_WS[Normalize Whitespace]
|
|
|
|
|
NORMALIZE_WS --> CASE_NORM[Lowercase Keywords]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
subgraph "Large Query Optimization"
|
|
|
|
|
LARGE_QUERY --> THREAD_POOL[4 Digest Threads]
|
|
|
|
|
THREAD_POOL --> CHUNK[Process in Chunks]
|
|
|
|
|
CHUNK --> PARALLEL_HASH[Parallel SpookyV2]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
CASE_NORM --> HASH_INPUT[Normalized Query Text]
|
|
|
|
|
PARALLEL_HASH --> HASH_INPUT
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
subgraph "SpookyV2 Hashing"
|
|
|
|
|
HASH_INPUT --> SPOOKY_INIT[SpookyHash::Init()]
|
|
|
|
|
SPOOKY_INIT --> SPOOKY_UPDATE[SpookyHash::Update(data, len)]
|
|
|
|
|
SPOOKY_UPDATE --> SPOOKY_FINAL[SpookyHash::Final(&hash1, &hash2)]
|
|
|
|
|
SPOOKY_FINAL --> DIGEST[64-bit Digest Value]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
subgraph "Digest Storage"
|
|
|
|
|
DIGEST --> STATS_TABLE[stats_mysql_query_digest]
|
|
|
|
|
DIGEST --> QUERY_CACHE_KEY[Cache Key]
|
|
|
|
|
DIGEST --> RULE_MATCHING[Rule Digest Match]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
style QUERY fill:#e1f5fe
|
|
|
|
|
style THREAD_POOL fill:#fff3e0
|
|
|
|
|
style DIGEST fill:#c8e6c9
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
### Query Normalization Known Issues
|
|
|
|
|
|
|
|
|
|
```mermaid
|
|
|
|
|
graph TB
|
|
|
|
|
subgraph "Known Query Digest Bugs"
|
|
|
|
|
BUG1[Bug: INSERT normalization<br/>INSERT INTO t VALUES (1),(2)]
|
|
|
|
|
BUG2[Bug: IN clause ordering<br/>WHERE id IN (3,1,2)]
|
|
|
|
|
BUG3[Bug: Float normalization<br/>1.5 vs 1.50]
|
|
|
|
|
BUG4[Bug: String escape<br/>'O\'Brien' vs 'O''Brien']
|
|
|
|
|
BUG5[Bug: Comment stripping<br/>/* comment */ variations]
|
|
|
|
|
BUG6[Bug: Whitespace handling<br/>Tab vs Space]
|
|
|
|
|
BUG7[Bug: Case sensitivity<br/>SELECT vs select in strings]
|
|
|
|
|
BUG8[Bug: Numeric formats<br/>0x1A vs 26]
|
|
|
|
|
BUG9[Bug: NULL handling<br/>IS NULL variations]
|
|
|
|
|
BUG10[Bug: Operator spacing<br/>a=1 vs a = 1]
|
|
|
|
|
BUG11[Bug: Subquery formatting]
|
|
|
|
|
BUG12[Bug: JOIN reordering]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
subgraph "Impact on Caching"
|
|
|
|
|
BUG1 --> CACHE_MISS[Cache Misses]
|
|
|
|
|
BUG2 --> CACHE_MISS
|
|
|
|
|
BUG3 --> CACHE_MISS
|
|
|
|
|
BUG4 --> CACHE_MISS
|
|
|
|
|
|
|
|
|
|
CACHE_MISS --> PERF_IMPACT[Performance Impact]
|
|
|
|
|
CACHE_MISS --> STATS_SKEW[Statistics Skew]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
style BUG1 fill:#ffebee
|
|
|
|
|
style CACHE_MISS fill:#fff3e0
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
## SSL/TLS Implementation
|
|
|
|
|
|
|
|
|
|
### Non-Standard mTLS Flow
|
|
|
|
|
|
|
|
|
|
```mermaid
|
|
|
|
|
sequenceDiagram
|
|
|
|
|
participant C as Client
|
|
|
|
|
participant P as ProxySQL
|
|
|
|
|
participant B as Backend MySQL
|
|
|
|
|
|
|
|
|
|
Note over C,P: Frontend SSL (Standard)
|
|
|
|
|
C->>P: TCP Connect
|
|
|
|
|
P->>C: MySQL Greeting (SSL Capable)
|
|
|
|
|
C->>P: SSL Request
|
|
|
|
|
P->>C: SSL Handshake
|
|
|
|
|
C->>P: Client Certificate
|
|
|
|
|
P->>P: Verify Client Cert
|
|
|
|
|
P->>C: SSL Established
|
|
|
|
|
|
|
|
|
|
Note over C,P: Authentication Phase
|
|
|
|
|
C->>P: MySQL Handshake
|
|
|
|
|
P->>P: Extract Username
|
|
|
|
|
|
|
|
|
|
Note over P,B: Backend SSL (Non-Standard)
|
|
|
|
|
P->>B: TCP Connect
|
|
|
|
|
B->>P: MySQL Greeting
|
|
|
|
|
P->>B: SSL Request
|
|
|
|
|
B->>P: SSL Handshake Start
|
|
|
|
|
|
|
|
|
|
rect rgb(255, 230, 230)
|
|
|
|
|
Note over P,B: Non-Standard Behavior
|
|
|
|
|
P->>B: Client Certificate
|
|
|
|
|
B->>P: SSL Established
|
|
|
|
|
B->>P: Request MySQL Auth
|
|
|
|
|
P->>B: MySQL Handshake
|
|
|
|
|
P->>P: Post-Handshake Validation
|
|
|
|
|
P->>P: Match Frontend Username
|
|
|
|
|
P->>P: Verify Cert CN/SAN
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
alt Validation Success
|
|
|
|
|
P->>B: Complete Auth
|
|
|
|
|
B->>P: OK Packet
|
|
|
|
|
else Validation Failure
|
|
|
|
|
P->>P: Close Backend
|
|
|
|
|
P->>C: Error Response
|
|
|
|
|
end
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
### SPIFFE Certificate Flow
|
|
|
|
|
|
|
|
|
|
```mermaid
|
|
|
|
|
graph TB
|
|
|
|
|
subgraph "SPIFFE Authentication"
|
|
|
|
|
CLIENT[Client with SPIFFE Cert] --> EXTRACT_URI[Extract SPIFFE URI]
|
|
|
|
|
EXTRACT_URI --> PARSE_URI[Parse spiffe://domain/path]
|
|
|
|
|
|
|
|
|
|
PARSE_URI --> VALIDATE{Validate Format}
|
|
|
|
|
VALIDATE -->|Valid| CHECK_MAPPING[Check URI Mapping]
|
|
|
|
|
VALIDATE -->|Invalid| REJECT[Reject Connection]
|
|
|
|
|
|
|
|
|
|
CHECK_MAPPING --> MAP_TABLE[SPIFFE → Username Map]
|
|
|
|
|
MAP_TABLE --> FOUND{Mapping Found?}
|
|
|
|
|
|
|
|
|
|
FOUND -->|Yes| SET_USER[Set MySQL Username]
|
|
|
|
|
FOUND -->|No| DEFAULT_USER[Use Default/Reject]
|
|
|
|
|
|
|
|
|
|
SET_USER --> AUTH_BACKEND[Authenticate to Backend]
|
|
|
|
|
DEFAULT_USER --> AUTH_BACKEND
|
|
|
|
|
end
|
|
|
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|
|
subgraph "Certificate Validation"
|
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|
|
AUTH_BACKEND --> VERIFY_CHAIN[Verify Cert Chain]
|
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|
|
VERIFY_CHAIN --> CHECK_EXPIRY[Check Expiration]
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|
|
CHECK_EXPIRY --> CHECK_REVOKE[Check Revocation]
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|
|
CHECK_REVOKE --> VALIDATED[Certificate Valid]
|
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|
|
|
end
|
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|
|
style CLIENT fill:#e1f5fe
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style VALIDATED fill:#c8e6c9
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style REJECT fill:#ffebee
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|
```
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|
|
## Cluster Synchronization Details
|
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|
|
### Differential Sync Algorithm
|
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|
|
|
```mermaid
|
|
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|
|
graph TB
|
|
|
|
|
subgraph "Checksum Calculation Per Module"
|
|
|
|
|
subgraph "Module: mysql_servers"
|
|
|
|
|
S_QUERY[SELECT * FROM mysql_servers] --> S_HASH[SpookyV2 Hash]
|
|
|
|
|
S_HASH --> S_CHECK[Checksum: 0xABCD1234]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
subgraph "Module: mysql_users"
|
|
|
|
|
U_QUERY[SELECT * FROM mysql_users] --> U_HASH[SpookyV2 Hash]
|
|
|
|
|
U_HASH --> U_CHECK[Checksum: 0xDEAD5678]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
subgraph "Module: mysql_query_rules"
|
|
|
|
|
Q_QUERY[SELECT * FROM mysql_query_rules] --> Q_HASH[SpookyV2 Hash]
|
|
|
|
|
Q_HASH --> Q_CHECK[Checksum: 0xBEEF9012]
|
|
|
|
|
end
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
subgraph "Sync Decision Logic"
|
|
|
|
|
S_CHECK --> COMPARE_S{Compare with Peers}
|
|
|
|
|
U_CHECK --> COMPARE_U{Compare with Peers}
|
|
|
|
|
Q_CHECK --> COMPARE_Q{Compare with Peers}
|
|
|
|
|
|
|
|
|
|
COMPARE_S -->|Different| S_DIFF[Calculate Diff Count]
|
|
|
|
|
COMPARE_U -->|Different| U_DIFF[Calculate Diff Count]
|
|
|
|
|
COMPARE_Q -->|Different| Q_DIFF[Calculate Diff Count]
|
|
|
|
|
|
|
|
|
|
S_DIFF --> S_THRESH{Diff > mysql_servers_diffs_before_sync?}
|
|
|
|
|
U_DIFF --> U_THRESH{Diff > mysql_users_diffs_before_sync?}
|
|
|
|
|
Q_DIFF --> Q_THRESH{Diff > mysql_query_rules_diffs_before_sync?}
|
|
|
|
|
|
|
|
|
|
S_THRESH -->|Yes| S_SYNC[Sync mysql_servers]
|
|
|
|
|
U_THRESH -->|Yes| U_SYNC[Sync mysql_users]
|
|
|
|
|
Q_THRESH -->|Yes| Q_SYNC[Sync mysql_query_rules]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
subgraph "Sync Execution"
|
|
|
|
|
S_SYNC --> FETCH_S[Fetch from Peer with Higher Epoch]
|
|
|
|
|
U_SYNC --> FETCH_U[Fetch from Peer with Higher Epoch]
|
|
|
|
|
Q_SYNC --> FETCH_Q[Fetch from Peer with Higher Epoch]
|
|
|
|
|
|
|
|
|
|
FETCH_S --> APPLY_S[Apply to Runtime]
|
|
|
|
|
FETCH_U --> APPLY_U[Apply to Runtime]
|
|
|
|
|
FETCH_Q --> APPLY_Q[Apply to Runtime]
|
|
|
|
|
|
|
|
|
|
APPLY_S --> PERSIST[Save to Disk]
|
|
|
|
|
APPLY_U --> PERSIST
|
|
|
|
|
APPLY_Q --> PERSIST
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
style S_CHECK fill:#e1f5fe
|
|
|
|
|
style U_CHECK fill:#e8f5e8
|
|
|
|
|
style Q_CHECK fill:#fff3e0
|
|
|
|
|
style PERSIST fill:#c8e6c9
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
### Cluster Node Communication
|
|
|
|
|
|
|
|
|
|
```mermaid
|
|
|
|
|
sequenceDiagram
|
|
|
|
|
participant N1 as Node 1 (Leader)
|
|
|
|
|
participant N2 as Node 2
|
|
|
|
|
participant N3 as Node 3
|
|
|
|
|
|
|
|
|
|
Note over N1,N3: Periodic Sync Check (5s default)
|
|
|
|
|
|
|
|
|
|
N1->>N2: Request Checksums
|
|
|
|
|
N1->>N3: Request Checksums
|
|
|
|
|
|
|
|
|
|
N2->>N1: Response {epoch:100, checksums:[...]}
|
|
|
|
|
N3->>N1: Response {epoch:99, checksums:[...]}
|
|
|
|
|
|
|
|
|
|
N1->>N1: Compare Checksums
|
|
|
|
|
|
|
|
|
|
alt Checksums Differ
|
|
|
|
|
N1->>N1: Check Diff Counts
|
|
|
|
|
|
|
|
|
|
alt Diff > Threshold
|
|
|
|
|
N1->>N2: Request Full Data
|
|
|
|
|
N2->>N1: Send mysql_servers rows
|
|
|
|
|
N1->>N1: Apply Changes
|
|
|
|
|
|
|
|
|
|
N1->>N3: Push Updates
|
|
|
|
|
N3->>N3: Apply Changes
|
|
|
|
|
else Diff < Threshold
|
|
|
|
|
N1->>N1: Increment Counter
|
|
|
|
|
N1->>N1: Wait Next Cycle
|
|
|
|
|
end
|
|
|
|
|
else Checksums Match
|
|
|
|
|
N1->>N1: No Action Needed
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
Note over N1,N3: Update Global Checksum
|
|
|
|
|
N1->>N2: Broadcast Global Checksum
|
|
|
|
|
N1->>N3: Broadcast Global Checksum
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
## Read-Only Server Management
|
|
|
|
|
|
|
|
|
|
### Evolution of Read-Only Handling
|
|
|
|
|
|
|
|
|
|
```mermaid
|
|
|
|
|
graph TB
|
|
|
|
|
subgraph "Legacy Mode (Pre-2.5.1)"
|
|
|
|
|
L_CHECK[Check read_only] --> L_BINARY{Binary Decision}
|
|
|
|
|
L_BINARY -->|read_only=0| L_WRITER[Assign to Writer HG]
|
|
|
|
|
L_BINARY -->|read_only=1| L_READER[Assign to Reader HG]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
subgraph "Modern Mode (2.5.1+)"
|
|
|
|
|
M_CHECK[Check Multiple Variables] --> M_EVAL[Weighted Evaluation]
|
|
|
|
|
|
|
|
|
|
subgraph "Variables Checked"
|
|
|
|
|
V1[read_only: weight 100]
|
|
|
|
|
V2[innodb_read_only: weight 1000]
|
|
|
|
|
V3[super_read_only: weight 10000]
|
|
|
|
|
V4[innodb_super_read_only: custom]
|
|
|
|
|
V5[aws_aurora_info: custom]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
V1 --> M_EVAL
|
|
|
|
|
V2 --> M_EVAL
|
|
|
|
|
V3 --> M_EVAL
|
|
|
|
|
V4 --> M_EVAL
|
|
|
|
|
V5 --> M_EVAL
|
|
|
|
|
|
|
|
|
|
M_EVAL --> SCORE[Calculate Total Score]
|
|
|
|
|
SCORE --> DECISION{Score Evaluation}
|
|
|
|
|
|
|
|
|
|
DECISION -->|Score = 0| ASSIGN_WRITER[To Writer HG]
|
|
|
|
|
DECISION -->|Score > 0| ASSIGN_READER[To Reader HG]
|
|
|
|
|
DECISION -->|Aurora Writer| FORCE_WRITER[Override: Writer]
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
subgraph "Aurora Special Handling"
|
|
|
|
|
V5 --> AURORA_CHECK{Is Aurora?}
|
|
|
|
|
AURORA_CHECK -->|Yes| PARSE_JSON[Parse JSON Info]
|
|
|
|
|
PARSE_JSON --> CHECK_ROLE{Check Role}
|
|
|
|
|
CHECK_ROLE -->|WRITER| FORCE_WRITER
|
|
|
|
|
CHECK_ROLE -->|READER| ASSIGN_READER
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
style L_BINARY fill:#ffebee
|
|
|
|
|
style M_EVAL fill:#e8f5e8
|
|
|
|
|
style AURORA_CHECK fill:#e1f5fe
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
## Performance Optimization Points
|
|
|
|
|
|
|
|
|
|
### Performance Optimizations
|
|
|
|
|
|
noizu
8 months ago