> -----Original Message----- > From: Andi Kleen [mailto:[EMAIL PROTECTED] > Sent: Wednesday, October 10, 2007 9:02 AM > To: Waskiewicz Jr, Peter P > Cc: David Miller; [EMAIL PROTECTED]; [EMAIL PROTECTED]; > [EMAIL PROTECTED]; [EMAIL PROTECTED]; > [EMAIL PROTECTED]; [EMAIL PROTECTED]; > [EMAIL PROTECTED]; [EMAIL PROTECTED]; > netdev@vger.kernel.org; [EMAIL PROTECTED]; > [EMAIL PROTECTED]; [EMAIL PROTECTED]; > [EMAIL PROTECTED]; [EMAIL PROTECTED]; > [EMAIL PROTECTED]; [EMAIL PROTECTED]; [EMAIL PROTECTED]; > [EMAIL PROTECTED] > Subject: Re: [ofa-general] Re: [PATCH 2/3][NET_BATCH] net > core use batching > > > We've done similar testing with ixgbe to push maximum descriptor > > counts, and we lost performance very quickly in the same > range you're > > quoting on NIU. > > Did you try it with WC writes to the ring or CLFLUSH? > > -Andi
Hmm, I think it might be slightly different, but it still shows queue depth vs. performance. I was actually referring to how many descriptors we can represent a packet with before it becomes a problem wrt performance. This morning I tried to actually push my ixgbe NIC hard enough to come close to filling the ring with packets (384-byte packets), and even on my 8-core Xeon I can't do it. My system can't generate enough I/O to fill the hardware queues before CPUs max out. -PJ Waskiewicz - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
