Consolidate config docs in config.md, update file references

config.md

@@ -14,13 +14,17 @@ By default, WeaselDB looks for `config.toml` in the current directory. You can s
 
 ### Server Configuration (`[server]`)
 
-Controls basic server binding and request limits.
+Controls server networking, threading, and request handling behavior.
 
 | Parameter | Type | Default | Description |
 |-----------|------|---------|-------------|
 | `bind_address` | string | `"127.0.0.1"` | IP address to bind the server to |
 | `port` | integer | `8080` | Port number to listen on |
 | `max_request_size_bytes` | integer | `1048576` (1MB) | Maximum size for incoming requests. Requests exceeding this limit receive a `413 Content Too Large` response |
+| `accept_threads` | integer | `1` | Number of dedicated threads for accepting incoming connections |
+| `network_threads` | integer | `1` | Number of threads for epoll-based network I/O processing |
+| `event_batch_size` | integer | `32` | Number of events to process in each epoll batch |
+| `max_connections` | integer | `1000` | Maximum number of concurrent connections (0 = unlimited) |
 
 ### Commit Configuration (`[commit]`)
 
@@ -50,6 +54,10 @@ Controls behavior of the `/v1/subscribe` endpoint and SSE streaming.
 bind_address = "0.0.0.0"
 port = 8080
 max_request_size_bytes = 2097152  # 2MB
+accept_threads = 2
+network_threads = 8
+event_batch_size = 64
+max_connections = 10000
 
 [commit]
 min_request_id_length = 32
@@ -63,15 +71,69 @@ keepalive_interval_seconds = 15
 
 ## Configuration Loading
 
-- If the specified config file doesn't exist or contains errors, WeaselDB will use default values and log a warning
-- All configuration parameters are optional - any missing values will use the defaults shown above
+WeaselDB uses the `toml11` library for configuration parsing with robust error handling:
+
+- **File Loading**: Uses `ConfigParser::load_from_file(path)` to parse TOML files
+- **Fallback Behavior**: If the config file doesn't exist or contains errors, WeaselDB uses default values and logs a warning
+- **Optional Parameters**: All configuration parameters are optional - missing values use the defaults shown above
+- **Type Safety**: Configuration values are parsed with type validation and meaningful error messages
+- **Validation**: All parameters are validated against reasonable bounds before use
 
 ## API Relationship
 
-These configuration parameters directly affect API behavior:
+These configuration parameters directly affect server and API behavior:
 
+**Server Performance:**
+- **`accept_threads`**: Controls parallelism for accepting new connections. More threads can handle higher connection rates
+- **`network_threads`**: Controls I/O processing parallelism. Should typically match CPU core count for optimal performance
+- **`event_batch_size`**: Larger batches reduce syscall overhead but may increase latency under light load
+- **`max_connections`**: Prevents resource exhaustion by limiting concurrent connections
+
+**Request Handling:**
 - **`max_request_size_bytes`**: Determines when `/v1/commit` returns `413 Content Too Large`
-- **`min_request_id_length`**: Validates `request_id` fields in `/v1/commit` requests
+- **`min_request_id_length`**: Validates `request_id` fields in `/v1/commit` requests for sufficient entropy
+
+**Request ID Management:**
 - **`request_id_retention_*`**: Affects availability of data for `/v1/status` queries and likelihood of `log_truncated` responses
+
+**Subscription Streaming:**
 - **`max_buffer_size_bytes`**: Controls when `/v1/subscribe` connections are terminated due to slow consumption
 - **`keepalive_interval_seconds`**: Frequency of keepalive comments in `/v1/subscribe` streams
+
+## Configuration Validation
+
+The configuration system includes comprehensive validation with specific bounds checking:
+
+### Server Configuration Limits
+- **`port`**: Must be between 1 and 65535
+- **`max_request_size_bytes`**: Must be > 0 and ≤ 100MB
+- **`accept_threads`**: Must be between 1 and 100
+- **`network_threads`**: Must be between 1 and 1000
+- **`event_batch_size`**: Must be between 1 and 10000
+- **`max_connections`**: Must be between 0 and 100000 (0 = unlimited)
+
+### Commit Configuration Limits
+- **`min_request_id_length`**: Must be between 8 and 256 characters
+- **`request_id_retention_hours`**: Must be between 1 and 8760 hours (1 year)
+- **`request_id_retention_versions`**: Must be > 0
+
+### Subscription Configuration Limits
+- **`max_buffer_size_bytes`**: Must be > 0 and ≤ 1GB
+- **`keepalive_interval_seconds`**: Must be between 1 and 3600 seconds (1 hour)
+
+### Cross-Validation
+- Warns if `max_request_size_bytes` > `max_buffer_size_bytes` (potential buffering issues)
+
+## Configuration Management
+
+### Code Integration
+- **Configuration Structure**: Defined in `src/config.hpp` with structured types
+- **Parser Implementation**: Located in `src/config.cpp` using template-based parsing
+- **Default Values**: Embedded as struct defaults for compile-time initialization
+- **Runtime Usage**: Configuration passed to server components during initialization
+
+### Development Guidelines
+- **New Parameters**: Add to appropriate struct in `src/config.hpp`
+- **Validation**: Include bounds checking in `ConfigParser::validate_config()`
+- **Documentation**: Update this file when adding new configuration options
+- **Testing**: Verify both valid and invalid configuration scenarios