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From: Tianyang Chen <tianyangpenn@gmail.com>
To: xen-devel@lists.xen.org
Cc: dario.faggioli@citrix.com, xumengpanda@gmail.com,
	Tianyang Chen <tianyangpenn@gmail.com>
Subject: [PATCH] sched_rt: Improved nested virtualization performance
Date: Wed, 18 Nov 2015 22:50:21 -0500	[thread overview]
Message-ID: <1447905022-5633-1-git-send-email-tianyangpenn@gmail.com> (raw)

In nested virtualization, choosing the smaller value for the
time slice between the MAX_SCHEDULE and the budget will cause
high host CPU usage.

Signed-off-by: Tianyang Chen <tianyangpenn@gmail.com>
---
 xen/common/sched_rt.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/common/sched_rt.c b/xen/common/sched_rt.c
index 4372486..9da3f35 100644
--- a/xen/common/sched_rt.c
+++ b/xen/common/sched_rt.c
@@ -889,7 +889,7 @@ rt_schedule(const struct scheduler *ops, s_time_t now, bool_t tasklet_work_sched
         }
     }
 
-    ret.time = MIN(snext->budget, MAX_SCHEDULE); /* sched quantum */
+    ret.time = MAX_SCHEDULE; /*should be used in nested virtualization*/
     ret.task = snext->vcpu;
 
     /* TRACE */
-- 
1.7.9.5

             reply	other threads:[~2015-11-19  3:50 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-19  3:50 Tianyang Chen [this message]
2015-11-19  3:59 ` [PATCH] sched_rt: Improved nested virtualization performance Meng Xu
     [not found] <1447903458-4736-1-git-send-email-tianyangpenn@gmail.com>
     [not found] ` <CAENZ-+=T-t-vxYVKb-OSc0rjkRSriHvrBx8DjeCb2GKu1hFs8w@mail.gmail.com>
2015-11-19  9:51   ` Dario Faggioli
2015-11-19 15:01     ` Meng Xu

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