netdev - Re: Network performance with small packets

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1299694560.25664.125.camel@localhost.localdomain>
Date:	Wed, 09 Mar 2011 10:16:00 -0800
From:	Shirley Ma <mashirle@...ibm.com>
To:	"Michael S. Tsirkin" <mst@...hat.com>
Cc:	Tom Lendacky <tahm@...ux.vnet.ibm.com>,
	Rusty Russell <rusty@...tcorp.com.au>,
	Krishna Kumar2 <krkumar2@...ibm.com>,
	David Miller <davem@...emloft.net>, kvm@...r.kernel.org,
	netdev@...r.kernel.org, steved@...ibm.com
Subject: Re: Network performance with small packets - continued

On Wed, 2011-03-09 at 19:16 +0200, Michael S. Tsirkin wrote:
> On Wed, Mar 09, 2011 at 08:51:33AM -0800, Shirley Ma wrote:
> > On Wed, 2011-03-09 at 10:09 -0600, Tom Lendacky wrote:
> > > > > Vhost is receiving a lot of notifications for packets that are
> to
> > > be
> > > > > transmitted (over 60% of the packets generate a kick_notify). 
> > 
> > This is guest TX send notification when vhost enables notification.
> > 
> > In TCP_STREAM test, vhost exits from reaching NAPI WEIGHT,
> 
> 
> You mean virtio?

Sorry, I messed up NAPI WEIGHT and VHOST NET WEIGHT.

I meant VHOST_NET_WEIGH, vhost exit handdle_tx() from VHOST NET WEIGHT
w/o enabling notification.

> 
> > it rarely
> > enables the notification, vhost re-enters handle_tx from NAPI poll,
> 
> Does NAPI really call handle_tx? Not rx? 

I meant for TX/RX, vhost re-enter handle_tx from vhost_poll_queue() not
from kick_notify.

Shirley

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html