netdev - Re: what is the expeted performance from a dual port 10G card ?

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 for Android: free password hash cracker in your pocket

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

Message-ID: <20081128135419.GH32518@solarflare.com>
Date:	Fri, 28 Nov 2008 13:54:20 +0000
From:	Ben Hutchings <bhutchings@...arflare.com>
To:	Raz <raziebe@...il.com>
Cc:	netdev@...r.kernel.org
Subject: Re: what is the expeted performance from a dual port 10G card ?

Raz wrote:
> Hello
> I have been testing 10G ethernet cards , intel ixgbe, chelsio, tehuti
> and melanox . All are dual port cards.
> I have used pktgen to test it. A single cpu is mapped over a single
> interface (no neeed for MQ , which is quite bad anyway).
> Results:
> Intel gives: 13Gbps , 6.5 from each port.
> The rest give ~10 Gbps .
> Cards were tested on PCI-E x8 slot, on a supermicro x7DBI and
> supermicro 1025W-UR.
> 
> Am i to expect ~20Gbps from each card ?

PCI Express provides 2.5 Gbps per lane (can be 5 Gbps in PCIe 2.0 but
that's quite new).  So an x8 slot is limited to 20 Gbps including all
the PCIe protocol overhead, which can be substantial.  You will not
get 20 Gbps out of dual-port cards without doubling the width or lane
speed.

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.
--
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