fix: lower Solana default concurrency, comment out broken Polygon RPCs

- Set Solana DEFAULT_MAX_CONCURRENT to 1 (public RPCs rate-limit hard)
- Add max_concurrent=1 + rpc_delay_ms=500 in example configs
- Comment out Polygon chain (public RPCs require API keys)
- Remove duplicate Base auto-detection example from README

Author: maxylev

Config.toml.example

@@ -17,19 +17,21 @@ rpc = [
 start_block = 12000000
 end_block = 12000500
 
-[[chains]]
-caip2 = "eip155:137"
-rpc = [
-    "https://polygon-rpc.com",
-    "https://rpc.ankr.com/polygon",
-]
-end_block = 55000500
+# Polygon public RPCs often require API keys. Commented out by default.
+# [[chains]]
+# caip2 = "eip155:137"
+# rpc = [
+#     "https://polygon-rpc.com",
+#     "https://rpc.ankr.com/polygon",
+# ]
 
 [[chains]]
 caip2 = "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"
 rpc = [
     "https://api.mainnet-beta.solana.com",
 ]
+max_concurrent = 1
+rpc_delay_ms = 500
 
 [assets.ETH_NATIVE]
 network = "eip155:1"
@@ -46,16 +48,6 @@ network = "eip155:8453"
 contract = "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
 decimals = 6
 
-[assets.MATIC_NATIVE]
-network = "eip155:137"
-contract = "native"
-decimals = 18
-
-[assets.USDC_POLY]
-network = "eip155:137"
-contract = "0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174"
-decimals = 6
-
 [assets.SOL_NATIVE]
 network = "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"
 contract = "native"

README.md

@@ -132,21 +132,18 @@ start_block = 12000000
 end_block = 12000500
 
 # Omit both start_block and end_block → scans last 1,000 blocks (EVM) / 500 slots (Solana) / 6 blocks (Bitcoin)
-[[chains]]
-caip2 = "eip155:137"
-rpc = ["https://polygon-rpc.com"]
-
-# Omit only end_block → scans from start_block to the node's latest block
-[[chains]]
-caip2 = "eip155:8453"
-rpc = ["https://mainnet.base.org"]
-start_block = 12000000
+# NOTE: Public Ethereum RPCs usually work. Polygon public RPCs often require API keys.
+# [[chains]]
+# caip2 = "eip155:137"
+# rpc = ["https://polygon-rpc.com"]
 
 [[chains]]
 caip2 = "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"
 rpc = ["https://api.mainnet-beta.solana.com"]
 start_block = 250000000
 end_block = 250000100
+max_concurrent = 1
+rpc_delay_ms = 500
 
 [[chains]]
 caip2 = "bip122:000000000019d6689c085ae165831e93"

src/solana.rs

@@ -10,7 +10,7 @@ use tokio::sync::Mutex;
 
 const SOL_DECIMALS: u32 = 9;
 const DEFAULT_RPC_DELAY_MS: u64 = 200;
-const DEFAULT_MAX_CONCURRENT: usize = 5;
+const DEFAULT_MAX_CONCURRENT: usize = 1;
 
 pub struct SolanaScanner {
     pub rpc_urls: Vec<String>,