OpenVZ Forum


Home » Mailing lists » Devel » [RFC][for -mm] memory controller enhancements for reclaiming take2 [0/8] introduction
[RFC][for -mm] memory controller enhancements for reclaiming take2 [8/8] wake up waiters at unchage [message #24218 is a reply to message #24210] Mon, 03 December 2007 09:45 Go to previous messageGo to previous message
KAMEZAWA Hiroyuki is currently offline  KAMEZAWA Hiroyuki
Messages: 463
Registered: September 2006
Senior Member
Throttling direct reclaim reduces the sytem load. But waiters are only waken
up if someone finish try_to_free_mem_cgroup_pages().

In progress of reclaiming, there can be enough memory before try_to_free_xxx
is finished. Because we throttle the number of reclaimers, it's better to
wake up waiters if there is enough room, in moderate way.
This decreases the system idle time under memory pressure in cgroup.

Signed-off-by: KAMEZAWA  Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>



 mm/memcontrol.c |    7 +++++++
 1 file changed, 7 insertions(+)

Index: linux-2.6.24-rc3-mm2/mm/memcontrol.c
===================================================================
--- linux-2.6.24-rc3-mm2.orig/mm/memcontrol.c
+++ linux-2.6.24-rc3-mm2/mm/memcontrol.c
@@ -816,6 +816,13 @@ void mem_cgroup_uncharge(struct page_cgr
 			__mem_cgroup_remove_list(pc);
 			spin_unlock_irqrestore(&mz->lru_lock, flags);
 			kfree(pc);
+			/*
+			 * If there is enough room but there are waiters,
+			 * wake up one. (wake up all is tend to be heavy)
+			 */
+			if (!res_counter_above_high_watermark(&mem->res) &&
+			     waitqueue_active(&mem->waitq))
+				wake_up(&mem->waitq);
 		}
 	}
 }

_______________________________________________
Containers mailing list
Containers@lists.linux-foundation.org
https://lists.linux-foundation.org/mailman/listinfo/containers
 
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Previous Topic: [PATCH 4/4] netns: prevent usage of flowi with not initialized fl_net in routing (v2)
Next Topic: Re: namespace support requires network modules to say "GPL"
Goto Forum:
  


Current Time: Fri Jul 25 14:41:26 GMT 2025

Total time taken to generate the page: 0.18376 seconds