On Thu, Apr 28, 2011 at 02:22:29PM -0700, Jack Vogel wrote: > My validation engineer set things up on an 8.2 REL system, testing the > equivalent of > HEAD, and he reports performance is fine. This is without any tweaks from > what's > checked in. > > Increasing the descriptors to 4K is way overkill and might actually cause > problems, > go back to default. > > He has a Linux test client, what are you transmitting to? > > Jack > > > On Thu, Apr 28, 2011 at 11:00 AM, Adam Stylinski > <kungfujesu...@gmail.com>wrote: > > > On Thu, Apr 28, 2011 at 09:52:14AM -0700, Jack Vogel wrote: > > > Adam, > > > > > > The TX ring for the legacy driver is small right now compared to em, try > > > this experiment, > > > edit if_lem.c, search for "lem_txd" and change EM_DEFAULT_TXD to 1024, > > see > > > what > > > that does, then 2048. > > > > > > My real strategy with the legacy code was that it should stable, meaning > > not > > > getting > > > a lot of changes... that really hasn't worked out over time. I suppose > > I'll > > > have to try and > > > give it some tweaks and let you try it. The problem with this code is it > > > technically supports > > > a huge range of old stuff we don't test any more, things I do might cause > > > other regressions :( > > > > > > Oh well, let me know if increasing the TX descriptors helps. > > > > > > Jack > > Jack, > > > > Is this the same thing as adjusting these values?: > > > > hw.em.rxd=4096 > > hw.em.txd=4096 > > > > If so I've maxed this out and it's not helping. I'll give it a shot on my > > 8-STABLE box as it has a kernel I can play with. > > > > Setting the MTU to 1500 gave lower throughput. > > > > -- > > Adam Stylinski > > PGP Key: http://pohl.ececs.uc.edu/~adam/publickey.pub > > Blog: http://technicallyliving.blogspot.com > >
I am transmitting to a linux client (kernel 2.6.38, 9000 byte MTU, PCI-Ex based
card). My sysctl's on the Linux client (apart from the default) look like so:
net.ipv4.ip_forward = 0
# Enables source route verification
net.ipv4.conf.default.rp_filter = 1
# Enable reverse path
net.ipv4.conf.all.rp_filter = 1
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 87380 16777216
net.core.wmem_default = 87380
net.core.rmem_default = 87380
net.ipv4.tcp_mem = 98304 131072 196608
net.ipv4.tcp_no_metrics_save = 1
net.ipv4.tcp_window_scaling = 1
dev.rtc.max-user-freq = 1024
The exact troublesome device (as reported by pciconf):
em0@pci0:7:5:0: class=0x020000 card=0x13768086 chip=0x107c8086 rev=0x05 hdr=0x00
vendor = 'Intel Corporation'
device = 'Gigabit Ethernet Controller (Copper) rev 5 (82541PI)'
class = network
subclass = ethernet
Apart from bus saturation (which I don't suspect is the problem) I'm not sure
what the issue could be. What should I try next?
--
Adam Stylinski
PGP Key: http://pohl.ececs.uc.edu/~adam/publickey.pub
Blog: http://technicallyliving.blogspot.com
pgp4gKNfa63Tq.pgp
Description: PGP signature
