/** The default memory limit, in megabytes: 50% of the machine's memory. */
export declare function defaultMemoryLimit(): number;
/** How often, in new states, the search looks at its memory: reading it costs a system call. */
export declare const MEMORY_EVERY = 4096;
/** Whether this process (all its threads) holds more than `limit` megabytes. */
export declare function overMemory(limit: number): boolean;