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  PHC 
Open Source and information security mailing list archives
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Thu, 22 Oct 2015 08:46:33 -0700
From:	Rick Jones <>
To:	"Michael S. Tsirkin" <>,
	Jason Wang <>
Subject: Re: [PATCH net-next RFC 2/2] vhost_net: basic polling support

On 10/22/2015 02:33 AM, Michael S. Tsirkin wrote:
> On Thu, Oct 22, 2015 at 01:27:29AM -0400, Jason Wang wrote:
>> This patch tries to poll for new added tx buffer for a while at the
>> end of tx processing. The maximum time spent on polling were limited
>> through a module parameter. To avoid block rx, the loop will end it
>> there's new other works queued on vhost so in fact socket receive
>> queue is also be polled.
>> busyloop_timeout = 50 gives us following improvement on TCP_RR test:
>> size/session/+thu%/+normalize%
>>      1/     1/   +5%/  -20%
>>      1/    50/  +17%/   +3%
> Is there a measureable increase in cpu utilization
> with busyloop_timeout = 0?

And since a netperf TCP_RR test is involved, be careful about what 
netperf reports for CPU util if that increase isn't in the context of 
the guest OS.

For completeness, looking at the effect on TCP_STREAM and TCP_MAERTS, 
aggregate _RR and even aggregate _RR/packets per second for many VMs on 
the same system would be in order.

happy benchmarking,

rick jones

To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to
More majordomo info at

Powered by blists - more mailing lists