Configuration

BookConfig

Field	Type	Constraint
order_pool_capacity	size_t	> 0
price_level_count	uint32_t	> 0
level_queue_capacity	uint32_t	> 0, power of two
max_order_id	uint64_t	< UINT64_MAX, allocatable as max_order_id + 1 locators

Construction throws std::invalid_argument when:

• Any dimension is zero
• level_queue_capacity is not a power of two
• price_level_count × level_queue_capacity overflows internal limits
• max_order_id is invalid for locator allocation

JSON loader

Implementation: src/core/config.cpp
Declaration: include/core/config.hpp

raijin::BookConfig config = raijin::load_config(path);

Schema

{
    "order_pool_capacity": 1000000,
    "price_level_count": 100000,
    "level_queue_capacity": 256,
    "max_order_id": 1000000
}

All keys required. Missing key: nlohmann::json::at() exception. Unopenable file: std::runtime_error.

Default path in src/main.cpp: config/settings.json.

Dimension sizing

Resource	Rule
Pool	order_pool_capacity per side; peak concurrent resting bids and asks separately
Locators	(max_order_id + 1) entries allocated regardless of active count
Level queue	Max distinct OrderRef slots per tick = level_queue_capacity
Ticks	External price maps to index: tick = (price - origin) / tick_size; require tick < price_level_count

Reference profiles

Profile	order_pool_capacity	price_level_count	level_queue_capacity	max_order_id
test::tiny_config()	8	256	4	64
test::small_config()	256	8192	64	4096
Benchmark default	100000	8192	512	500000
config/settings.json	1000000	100000	256	1000000

Receipt ring

Independent of BookConfig. Capacity must be a power of two.

RingBuffer<ExecutionReceipt> rb(65536);
LimitOrderBook book(config, &rb);

Size to peak fill burst between consumer drains. Full ring silently drops receipts.