Willy Tarreau bf883e0aa7 MAJOR: session: implement a wait-queue for sessions who need a buffer ... When a session_alloc_buffers() fails to allocate one or two buffers, it subscribes the session to buffer_wq, and waits for another session to release buffers. It's then removed from the queue and woken up with TASK_WAKE_RES, and can attempt its allocation again. We decide to try to wake as many waiters as we release buffers so that if we release 2 and two waiters need only once, they both have their chance. We must never come to the situation where we don't wake enough tasks up. It's common to release buffers after the completion of an I/O callback, which can happen even if the I/O could not be performed due to half a failure on memory allocation. In this situation, we don't want to move out of the wait queue the session that was just added, otherwise it will never get any buffer. Thus, we only force ourselves out of the queue when freeing the session. Note: at the moment, since session_alloc_buffers() is not used, no task is subscribed to the wait queue.		2014-12-24 23:47:33 +01:00
..
common	MEDIUM: buffer: implement b_alloc_margin()	2014-12-24 23:47:32 +01:00
import
proto	MAJOR: session: implement a wait-queue for sessions who need a buffer	2014-12-24 23:47:33 +01:00
types	MAJOR: session: implement a wait-queue for sessions who need a buffer	2014-12-24 23:47:33 +01:00