Function layer_trim_constraints

plugins/askrene/layer.c:1046–1100

}

size_t layer_trim_constraints(struct layer *layer, u64 cutoff)
{
	size_t num_removed = 0;
	struct constraint_hash_iter conit;
	struct constraint *con;
	struct bias_hash_iter biasit;
	struct bias *bias;
	struct node_bias_hash_iter node_it;
	struct node_bias *node_bias;

	for (con = constraint_hash_first(layer->constraints, &conit);
	     con;
	     con = constraint_hash_next(layer->constraints, &conit)) {
		if (con->timestamp < cutoff) {
			constraint_hash_delval(layer->constraints, &conit);
			tal_free(con);
			num_removed++;
		}
	}

	for (bias = bias_hash_first(layer->biases, &biasit); bias;
	     bias = bias_hash_next(layer->biases, &biasit)) {
		if (bias->timestamp < cutoff) {
			bias_hash_delval(layer->biases, &biasit);
			tal_free(bias);
			num_removed++;
		}
	}

	/* FIXME:
	 * Having both in_bias and out_bias bundled in the same node bias
	 * package help us save space. However we end up having a timestamp that
	 * applies to both biases and we lose precision in that.
	 * A possible pathological case is the following:
	 *      - in a certain moment we highly penalize a node A's outgoing
	 *      channels,
	 *      - then we often add or substract a small amount of bias to the
	 *      same node's incoming channels,
	 * As long as we keep updating the incoming channels biases the data
	 * timestamp will never grow old and we will never decay the outgoing
	 * bias that we set at the begining.
	 **/
	for (node_bias = node_bias_hash_first(layer->node_biases, &node_it);
	     node_bias;
	     node_bias = node_bias_hash_next(layer->node_biases, &node_it)) {
		if (node_bias->timestamp < cutoff) {
			node_bias_hash_delval(layer->node_biases, &node_it);
			tal_free(node_bias);
			num_removed++;
		}
	}

	save_complete_layer(layer);
	return num_removed;
}

void layer_add_disabled_node(struct layer *layer, const struct node_id *node)
{