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From: Ben Greear <greearb@candelatech•com>
To: Jesper Dangaard Brouer <brouer@redhat•com>
Cc: "David S. Miller" <davem@davemloft•net>,
	netdev@vger•kernel.org, Robert Olsson <robert@herjulf•se>
Subject: Re: [net-next PATCH] pktgen: add flag NO_TIMESTAMP to disable timestamping
Date: Wed, 01 Apr 2015 09:48:56 -0700	[thread overview]
Message-ID: <551C2178.9070000@candelatech.com> (raw)
In-Reply-To: <20140828161447.6652.59388.stgit@dragon>

On 08/28/2014 09:14 AM, Jesper Dangaard Brouer wrote:
> Then testing the TX limits of the stack, then it is useful to
> be-able to disable the do_gettimeofday() timetamping on every packet.
> 
> This implements a pktgen flag NO_TIMESTAMP which will disable this
> call to do_gettimeofday().
> 
> The performance change on (my system E5-2695) with skb_clone=0, goes
> from TX 2,423,751 pps to 2,567,165 pps with flag NO_TIMESTAMP. Thus,
> the cost of do_gettimeofday() or saving is approx 23 nanosec.
> 
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat•com>

> +		else if (strcmp(f, "NO_TIMESTAMP") == 0)
> +			pkt_dev->flags |= F_NO_TIMESTAMP;
> +

While porting pktgen changes into my own modified pktgen logic, I noticed
that there is no handling for !NO_TIMESTAMP, so it seems you cannot
disable this once it is enabled?

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech•com>
Candela Technologies Inc  http://www.candelatech.com

      parent reply	other threads:[~2015-04-01 16:48 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-08-28 16:14 [net-next PATCH] pktgen: add flag NO_TIMESTAMP to disable timestamping Jesper Dangaard Brouer
2014-08-29 16:17 ` Eric Dumazet
2014-08-29 19:02   ` Jesper Dangaard Brouer
2014-09-02  1:07 ` David Miller
2015-04-01 16:48 ` Ben Greear [this message]

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