From: Rusty Russell <rusty@rustcorp.com.au>
To: Avi Kivity <avi@qumranet.com>
Cc: Ingo Molnar <mingo@elte.hu>,
kvm-devel@lists.sourceforge.net, netdev <netdev@vger.kernel.org>
Subject: Re: [kvm-devel] QEMU PIC indirection patch for in-kernel APIC work
Date: Mon, 16 Apr 2007 10:22:46 +1000 [thread overview]
Message-ID: <1176682966.14322.193.camel@localhost.localdomain> (raw)
In-Reply-To: <461DA849.50406@qumranet.com>
On Thu, 2007-04-12 at 06:32 +0300, Avi Kivity wrote:
> I hadn't considered an always-blocking (or unbuffered) networking API.
> It's very counter to current APIs, but does make sense with things like
> syslets. Without syslets, I don't think it's very useful as you need
> some artificial threads to keep things humming along.
>
> (How would userspace specify it? O_DIRECT when opening the tap?)
TBH, I hadn't thought that far. Tap already has those IFF_NO_PI etc
flags, but it might make sense to just be the default. From userspace's
POV it's not a semantic change.
OK, just tested: I can get 230,000 packets (28 byte UDP) through the tun
device in a second (130,000 actually out the 100-base-T NIC, 100,000
dropped). If the tun driver's write() blocks until the skb is
destroyed, it's 4,000 packets.
So your intuition was right: skb_free latency on xmit (at least for this
e1000) is far too large for anything but an async solution.
Will ponder further.
Thanks!
Rusty.
next prev parent reply other threads:[~2007-04-16 0:23 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-04-02 11:46 QEMU PIC indirection patch for in-kernel APIC work Gregory Haskins
[not found] ` <4610A6A9.BA47.005A.0-Et1tbQHTxzrQT0dZR+AlfA@public.gmane.org>
2007-04-04 6:53 ` Avi Kivity
[not found] ` <46134B74.1080004-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-04 14:20 ` Anthony Liguori
[not found] ` <4613B438.60107-rdkfGonbjUSkNkDKm+mE6A@public.gmane.org>
2007-04-04 14:39 ` Avi Kivity
[not found] ` <4613B89F.8090806-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-04 14:55 ` Anthony Liguori
[not found] ` <4613BC6B.1070708-rdkfGonbjUSkNkDKm+mE6A@public.gmane.org>
2007-04-04 15:06 ` Avi Kivity
[not found] ` <4613BF07.50606-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-04 15:36 ` Nakajima, Jun
[not found] ` <8FFF7E42E93CC646B632AB40643802A8025B9580-1a9uaKK1+wJcIJlls4ac1rfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2007-04-04 15:47 ` Dor Laor
[not found] ` <64F9B87B6B770947A9F8391472E032160B318E96-yEcIvxbTEBqsx+V+t5oei8rau4O3wl8o3fe8/T/H7NteoWH0uzbU5w@public.gmane.org>
2007-04-04 15:53 ` Anthony Liguori
[not found] ` <4613C9EE.5030600-rdkfGonbjUSkNkDKm+mE6A@public.gmane.org>
2007-04-04 16:05 ` Avi Kivity
[not found] ` <4613CCD1.2070702-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-04 16:20 ` Nakajima, Jun
[not found] ` <8FFF7E42E93CC646B632AB40643802A8025B962E-1a9uaKK1+wJcIJlls4ac1rfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2007-04-04 16:27 ` Dor Laor
[not found] ` <64F9B87B6B770947A9F8391472E032160B318EDB-yEcIvxbTEBqsx+V+t5oei8rau4O3wl8o3fe8/T/H7NteoWH0uzbU5w@public.gmane.org>
2007-04-04 16:43 ` Anthony Liguori
[not found] ` <4613D596.7080201-rdkfGonbjUSkNkDKm+mE6A@public.gmane.org>
2007-04-04 16:54 ` Avi Kivity
2007-04-04 16:32 ` Avi Kivity
[not found] ` <4613D30E.7030905-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-04 16:48 ` Nakajima, Jun
[not found] ` <8FFF7E42E93CC646B632AB40643802A8025B96AA-1a9uaKK1+wJcIJlls4ac1rfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2007-04-04 16:58 ` Avi Kivity
[not found] ` <4613D93A.5020902-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-04 17:09 ` Nakajima, Jun
[not found] ` <8FFF7E42E93CC646B632AB40643802A8025B970D-1a9uaKK1+wJcIJlls4ac1rfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2007-04-04 21:33 ` Dor Laor
2007-04-04 18:12 ` Anthony Liguori
2007-04-04 15:51 ` Anthony Liguori
[not found] ` <4613C993.9020405-rdkfGonbjUSkNkDKm+mE6A@public.gmane.org>
2007-04-04 16:02 ` Avi Kivity
[not found] ` <4613CC01.1090500-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-04 16:09 ` Anthony Liguori
[not found] ` <4613CDB2.4000903-rdkfGonbjUSkNkDKm+mE6A@public.gmane.org>
2007-04-04 16:19 ` Avi Kivity
[not found] ` <4613D001.3040606-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-04 20:01 ` Ingo Molnar
[not found] ` <20070404200112.GA6070-X9Un+BFzKDI@public.gmane.org>
2007-04-04 20:24 ` Anthony Liguori
[not found] ` <4614098F.2030307-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
2007-04-04 21:21 ` Ingo Molnar
2007-04-04 23:19 ` [kvm-devel] " Rusty Russell
2007-04-05 7:17 ` Avi Kivity
2007-04-06 1:02 ` Rusty Russell
2007-04-08 5:36 ` Avi Kivity
[not found] ` <46187F4E.1080807-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-08 9:04 ` Muli Ben-Yehuda
2007-04-09 2:50 ` Rusty Russell
[not found] ` <1176087018.11664.65.camel-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org>
2007-04-09 7:10 ` Avi Kivity
[not found] ` <4619E6DC.3010804-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-09 9:46 ` Rusty Russell
[not found] ` <1176111984.11664.90.camel-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org>
2007-04-09 13:38 ` Avi Kivity
[not found] ` <461A41CA.9080201-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-10 8:07 ` Evgeniy Polyakov
2007-04-10 8:19 ` [kvm-devel] " Avi Kivity
[not found] ` <461B48A8.1060904-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-10 8:58 ` Evgeniy Polyakov
2007-04-10 11:21 ` [kvm-devel] " Avi Kivity
[not found] ` <461B7334.8090807-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-10 11:50 ` Evgeniy Polyakov
2007-04-10 12:17 ` [kvm-devel] " Avi Kivity
[not found] ` <461B8069.6070007-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-10 12:30 ` Evgeniy Polyakov
[not found] ` <20070410123034.GA11493-9fLWQ3dKdXwox3rIn2DAYQ@public.gmane.org>
2007-04-10 12:49 ` Avi Kivity
2007-04-11 3:53 ` [kvm-devel] " Rusty Russell
[not found] ` <1176263593.26372.84.camel-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org>
2007-04-11 4:26 ` Avi Kivity
[not found] ` <461C6360.1060908-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-11 13:23 ` Rusty Russell
[not found] ` <1176297794.14322.72.camel-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org>
2007-04-11 14:28 ` Avi Kivity
[not found] ` <461CF098.3090003-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-11 23:30 ` Rusty Russell
[not found] ` <1176334200.14322.133.camel-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org>
2007-04-12 3:32 ` Avi Kivity
2007-04-16 0:22 ` Rusty Russell [this message]
2007-04-16 5:13 ` [kvm-devel] " Avi Kivity
[not found] ` <1175728768.12230.593.camel-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org>
2007-04-05 9:30 ` Ingo Molnar
[not found] ` <20070405093033.GC25448-X9Un+BFzKDI@public.gmane.org>
2007-04-05 9:58 ` Avi Kivity
2007-04-05 10:26 ` [kvm-devel] " Ingo Molnar
2007-04-05 11:26 ` Avi Kivity
[not found] ` <4614DCE1.70905-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-05 11:36 ` Ingo Molnar
2007-04-06 1:16 ` [kvm-devel] " Rusty Russell
2007-04-06 18:59 ` Ingo Molnar
2007-04-05 10:55 ` Ingo Molnar
2007-04-05 14:32 ` [kvm-devel] " Anthony Liguori
2007-04-06 10:37 ` Ingo Molnar
2007-04-06 11:07 ` Ingo Molnar
2007-04-04 22:07 ` Dor Laor
2007-04-05 6:54 ` Avi Kivity
2007-04-05 6:40 ` Avi Kivity
2007-04-04 16:23 ` Dor Laor
[not found] ` <64F9B87B6B770947A9F8391472E032160B318ED4-yEcIvxbTEBqsx+V+t5oei8rau4O3wl8o3fe8/T/H7NteoWH0uzbU5w@public.gmane.org>
2007-04-04 16:48 ` Anthony Liguori
[not found] ` <4613D6CD.6060209-rdkfGonbjUSkNkDKm+mE6A@public.gmane.org>
2007-04-04 20:07 ` Ingo Molnar
2007-04-05 13:50 ` Dong, Eddie
[not found] ` <0E6FE5D295DE5B4B8D9070C26A227987E0D1EC-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2007-04-05 13:59 ` Avi Kivity
[not found] ` <461500B5.4080102-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-05 14:52 ` Dong, Eddie
[not found] ` <0E6FE5D295DE5B4B8D9070C26A227987F2444B-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2007-04-05 15:01 ` Avi Kivity
[not found] ` <46150F4F.4030505-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-04-05 15:16 ` Dong, Eddie
[not found] ` <0E6FE5D295DE5B4B8D9070C26A227987F24452-wq7ZOvIWXbNpB2pF5aRoyrfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2007-04-05 15:26 ` Anthony Liguori
2007-04-05 15:22 ` Anthony Liguori
2007-04-05 14:41 ` Dor Laor
[not found] ` <64F9B87B6B770947A9F8391472E032160B319509-yEcIvxbTEBqsx+V+t5oei8rau4O3wl8o3fe8/T/H7NteoWH0uzbU5w@public.gmane.org>
2007-04-05 14:48 ` Dong, Eddie
2007-04-05 14:57 ` Dong, Eddie
2007-04-04 17:51 ` Gregory Haskins
[not found] ` <46139F39.BA47.005A.0-Et1tbQHTxzrQT0dZR+AlfA@public.gmane.org>
2007-04-04 18:19 ` Anthony Liguori
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