# MEV Bot Analysis - November 9, 2025

## Executive Summary

**Bot Status:** ✅ RUNNING (Container: mev-bot-dev-master-dev)
**Health:** 🟡 OPERATIONAL but DEGRADED due to severe rate limiting
**Primary Issue:** Excessive 429 rate limit errors from public RPC endpoint

## Current Status

### Container Health
```
Container: mev-bot-dev-master-dev
Status: Up 7 minutes (healthy)
Branch: master-dev
Ports: 8080:8080, 9090:9090
Image: localhost/mev-bot:dev-master-dev
```

### Core Services Status
- ✅ MEV Bot Started Successfully
- ✅ Arbitrage Service Running
- ✅ Arbitrage Detection Engine Active
- ✅ Metrics Server Running (port 9090)
- ✅ Block Processing Active
- ✅ Pool Discovery Working
- ⚠️ RPC Connection SEVERELY RATE LIMITED

## Issues Identified

### 🔴 CRITICAL: RPC Rate Limiting

**Severity:** CRITICAL
**Impact:** HIGH - Degraded performance, missed opportunities

**Details:**
- **2,354 instances** of "429 Too Many Requests" errors in 7 minutes
- **Average:** ~5.6 rate limit errors per second
- **RPC Endpoint:** https://arb1.arbitrum.io/rpc (public, free tier)

**Error Examples:**
```
[ERROR] Failed to get L2 block 398369920: 429 Too Many Requests
[DEBUG] Registry 0x0000000022D53366457F9d5E68Ec105046FC4383 failed: 429 Too Many Requests
[DEBUG] Batch fetch attempt 1 failed with transient error: 429 Too Many Requests
```

**Root Cause:**
1. Using public RPC endpoint with very strict rate limits
2. Bot configured for 5 requests/second but public endpoint allows less
3. Concurrent queries to multiple registries (Curve, Uniswap, etc.)
4. Batch fetching generates multiple parallel requests

### 🟡 MEDIUM: Configuration Mismatch

**Current config.dev.yaml settings:**
```yaml
arbitrum:
  rpc_endpoint: "https://arb1.arbitrum.io/rpc"
  ws_endpoint: ""
  rate_limit:
    requests_per_second: 5    # Too high for public endpoint
    max_concurrent: 3
    burst: 10
```

**Current .env settings:**
```bash
# Has premium Chainstack endpoint but not being used!
ARBITRUM_RPC_ENDPOINT=https://arb1.arbitrum.io/rpc
# Premium endpoint commented out or unused
```

### 🟡 MEDIUM: Batch Fetch Failures

**Details:**
- ~200+ instances of "Failed to fetch batch 0-1: batch fetch V3 data failed after 3 attempts"
- Pools failing: Non-standard contracts and new/untested pools
- Blacklist growing: 907 total blacklisted pools

## Recommendations

### 1. 🔴 IMMEDIATE: Switch to Premium RPC Endpoint

**Action:** Use the Chainstack premium endpoint from .env

**Current .env has:**
```bash
ARBITRUM_RPC_ENDPOINT=https://arb1.arbitrum.io/rpc
ARBITRUM_WS_ENDPOINT=
```

**Need to check if there's a premium endpoint available** in environment or secrets.

**Implementation:**
```yaml
# config.dev.yaml
arbitrum:
  rpc_endpoint: "${CHAINSTACK_RPC_ENDPOINT:-https://arb1.arbitrum.io/rpc}"
```

### 2. 🟡 URGENT: Reduce Rate Limits

**Action:** Configure conservative rate limits for public endpoint

**Implementation:**
```yaml
# config.dev.yaml - for public endpoint
arbitrum:
  rate_limit:
    requests_per_second: 2    # Reduced from 5
    max_concurrent: 1         # Reduced from 3
    burst: 3                  # Reduced from 10
  fallback_endpoints:
    - url: "https://arbitrum-rpc.publicnode.com"
      rate_limit:
        requests_per_second: 1
        max_concurrent: 1
        burst: 2
```

### 3. 🟡 RECOMMENDED: Add More Fallback Endpoints

**Action:** Configure multiple fallback RPC endpoints

**Implementation:**
```yaml
fallback_endpoints:
  - url: "https://arbitrum-rpc.publicnode.com"
    rate_limit:
      requests_per_second: 1
      max_concurrent: 1
      burst: 2
  - url: "https://arb-mainnet.g.alchemy.com/v2/demo"
    rate_limit:
      requests_per_second: 1
      max_concurrent: 1
      burst: 2
  - url: "https://1rpc.io/arb"
    rate_limit:
      requests_per_second: 1
      max_concurrent: 1
      burst: 2
```

### 4. 🟢 OPTIMIZATION: Implement Exponential Backoff

**Action:** Enhance retry logic with exponential backoff

**Current:** Fixed retry delays (1s, 2s, 3s)
**Recommended:** Exponential backoff (1s, 2s, 4s, 8s, 16s)

### 5. 🟢 OPTIMIZATION: Cache Pool Data More Aggressively

**Action:** Increase cache expiration times

**Implementation:**
```yaml
uniswap:
  cache:
    enabled: true
    expiration: 600        # Increased from 300s to 10 minutes
    max_size: 2000        # Increased from 1000
```

### 6. 🟢 ENHANCEMENT: Reduce Curve Registry Queries

**Action:** Disable or limit Curve pool queries for now

Since Curve queries are generating many 429 errors and most Arbitrum volume is on Uniswap/Camelot, consider reducing Curve registry checks.

## Performance Metrics

### Block Processing
- **Blocks Processed:** ~1,000+ blocks in 7 minutes
- **Processing Rate:** ~2.4 blocks/second
- **Transaction Volume:** Processing 6-12 transactions per block
- **DEX Transactions:** Minimal DEX activity detected

### Error Rates
- **Rate Limit Errors:** 2,354 (avg 5.6/second)
- **Batch Fetch Failures:** ~200
- **Pool Blacklisted:** 907 total
- **Success Rate:** Low due to rate limiting

## Immediate Action Plan

### Priority 1: Fix Rate Limiting
```bash
# 1. Check for premium endpoint credentials
cat .env | grep -i chainstack
cat .env | grep -i alchemy
cat .env | grep -i infura

# 2. Update config with conservative limits
# Edit config/config.dev.yaml

# 3. Restart container
./scripts/dev-env.sh rebuild master-dev
```

### Priority 2: Monitor Improvements
```bash
# Watch for 429 errors
./scripts/dev-env.sh logs -f | grep "429"

# Check error rate
podman logs mev-bot-dev-master-dev 2>&1 | grep "429" | wc -l
```

### Priority 3: Optimize Configuration
- Reduce concurrent requests
- Increase cache times
- Add more fallback endpoints
- Implement smarter retry logic

## Positive Findings

Despite the rate limiting issues:
- ✅ Bot architecture is sound
- ✅ All services starting correctly
- ✅ Block processing working
- ✅ Pool discovery functional
- ✅ Arbitrage detection engine running
- ✅ Retry logic handling errors gracefully
- ✅ No crashes or panics
- ✅ Container healthy and stable

## Conclusion

**The bot is NOT stopped - it's running but severely degraded by rate limiting.**

The primary issue is using a public RPC endpoint that can't handle the bot's request volume. Switching to a premium endpoint or drastically reducing request rates will resolve the issue.

**Estimated Impact of Fixes:**
- 🔴 Switch to premium RPC → **95% error reduction**
- 🟡 Reduce rate limits → **70% error reduction**
- 🟢 Add fallbacks → **Better reliability**
- 🟢 Increase caching → **20% fewer requests**

**Next Steps:** Apply recommended fixes in priority order.