Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 14 Nov 2000 17:33:48 -0500
From:      David Jones <dej@inode.org>
To:        Jin Guojun (DSD staff) <jin@george.lbl.gov>, freebsd-hardware@FreeBSD.ORG
Subject:   Re: Luna 340
Message-ID:  <00111417334807.00296@coup.inode.org>
In-Reply-To: <200011141626.eAEGQoC27593@portnoy.lbl.gov>
References:  <200011141626.eAEGQoC27593@portnoy.lbl.gov>

next in thread | previous in thread | raw e-mail | index | archive | help
On November 14, 2000 11:26 am, Jin Guojun (DSD staff) wrote:

> The issue is that what will be the performance dropped if the card is
> plugged in a 32-bit 33 MHz PCI slot. According to the data sheet, the
> MD5 performance is 100 Mbps. On a 32-bit 33 MHz PCI system, it all mean=
s
> that the performance will be dropped to 50Mbps, right?

There are two factors involved here: the CPU power on the chip required t=
o do=20
MD5, and the PCI bus bandwidth required to transfer the information.

32-bit 33 MHz PCI has a theoretical throughput of 132 MBps, or just over =
1=20
Gbps.  This is more than enough to handle the MD5 requirement: 100 Mbps j=
ust=20
to suck the data in.  Note that you will never get near this in the real=20
world; PCI reads are slow.

The real issue is the performance on multiple streams of 3DES+MD5, which =
is=20
where the PCI system will be stressed.


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hardware" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?00111417334807.00296>