From: Alex Bligh <alex@alex.org.uk>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: netdev@vger.kernel.org,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Alex Bligh <alex@alex.org.uk>
Subject: Re: Scalability of interface creation and deletion
Date: Sun, 08 May 2011 10:35:02 +0100 [thread overview]
Message-ID: <F57561A93EFF5E88729A8D53@nimrod.local> (raw)
In-Reply-To: <1304838742.3207.45.camel@edumazet-laptop>
Eric,
--On 8 May 2011 09:12:22 +0200 Eric Dumazet <eric.dumazet@gmail.com> wrote:
> By the way, if I change HZ from 1000 to 100 I now have ten times slower
> result :
I repeated that test here. With HZ set to 1000 I got a total time of
4.022 seconds to remove 100 interfaces, of which:
Total 3.03808 Usage 199 Average 0.01527 elsewhere
Total 0.93992 Usage 200 Average 0.00470 synchronizing
as opposed to a total of 27.917 seconds with HZ set to 100, of which
Total 18.98515 Usage 199 Average 0.09540 elsewhere
Total 8.77581 Usage 200 Average 0.04388 synchronizing
Not quite a factor of 10 improvement, but nearly.
I have CONFIG_RCU_FAST_NO_HZ=y
I suspect this may just mean an rcu reader holds the rcu_read_lock
for a jiffies related time. Though I'm having difficulty seeing
what that might be on a system where the net is in essence idle.
--
Alex Bligh
next prev parent reply other threads:[~2011-05-08 9:35 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-07 11:08 Scalability of interface creation and deletion Alex Bligh
2011-05-07 12:22 ` Eric Dumazet
2011-05-07 15:26 ` Alex Bligh
2011-05-07 15:54 ` Eric Dumazet
2011-05-07 16:23 ` Ben Greear
2011-05-07 16:37 ` Eric Dumazet
2011-05-07 16:44 ` Ben Greear
2011-05-07 16:51 ` Eric Dumazet
2011-05-08 3:45 ` Ben Greear
2011-05-08 8:08 ` Alex Bligh
2011-05-09 21:46 ` Octavian Purdila
2011-05-07 16:26 ` Eric Dumazet
2011-05-07 18:24 ` Alex Bligh
2011-05-07 18:32 ` Eric Dumazet
2011-05-07 18:39 ` Eric Dumazet
2011-05-08 10:09 ` Alex Bligh
2011-05-07 18:42 ` Eric Dumazet
2011-05-07 18:50 ` Alex Bligh
2011-05-08 7:12 ` Eric Dumazet
2011-05-08 8:06 ` Alex Bligh
2011-05-08 9:35 ` Alex Bligh [this message]
2011-05-08 12:18 ` Alex Bligh
2011-05-08 12:50 ` Paul E. McKenney
2011-05-08 13:13 ` Alex Bligh
2011-05-08 13:44 ` Paul E. McKenney
2011-05-08 14:27 ` Alex Bligh
2011-05-08 14:47 ` Paul E. McKenney
2011-05-08 15:17 ` Alex Bligh
2011-05-08 15:48 ` Paul E. McKenney
2011-05-08 21:00 ` Eric Dumazet
2011-05-09 4:44 ` [PATCH] veth: use batched device unregister Eric Dumazet
2011-05-09 6:56 ` Michał Mirosław
2011-05-09 8:20 ` Eric Dumazet
2011-05-09 9:17 ` [PATCH net-next-2.6] net: use batched device unregister in veth and macvlan Eric Dumazet
2011-05-09 18:42 ` David Miller
2011-05-09 19:05 ` Eric Dumazet
2011-05-09 20:17 ` Eric Dumazet
2011-05-10 6:40 ` [PATCH net-2.6] vlan: fix GVRP at dismantle time Eric Dumazet
2011-05-10 19:23 ` David Miller
2011-05-09 7:45 ` [PATCH v2 net-next-2.6] veth: use batched device unregister Eric Dumazet
2011-05-09 9:22 ` Eric Dumazet
2011-05-09 5:37 ` Scalability of interface creation and deletion Alex Bligh
2011-05-09 6:37 ` Eric Dumazet
2011-05-09 7:11 ` Paul E. McKenney
2011-05-09 17:30 ` Jesse Gross
2011-05-08 12:44 ` Paul E. McKenney
2011-05-08 13:06 ` Alex Bligh
2011-05-08 13:14 ` Alex Bligh
2011-05-08 12:32 ` Paul E. McKenney
2011-05-07 18:51 ` Alex Bligh
2011-05-07 19:24 ` Eric Dumazet
2011-05-07 18:38 ` Alex Bligh
2011-05-07 18:44 ` Eric Dumazet
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