From: Bruce Allan Date: Wed, 6 Mar 2013 09:02:36 +0000 (+0000) Subject: e1000e: slow performance between two 82579 connected via 10Mbit hub X-Git-Tag: omap-for-v3.10/dt-fixes-for-merge-window~65^2~280^2~10 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=772d05c51c4f4896c120ad418b1e91144a2ac813;p=pandora-kernel.git e1000e: slow performance between two 82579 connected via 10Mbit hub Two 82579 LOMs connected via a 10Mb hub experience extraordinarily low performance. This is because 82579 is excessively aggressive on transmit at 10Mb half-duplex and will not provide sufficient time for the link partner to transmit. When the link partner is also 82579, the result is a lot of collisions (and corresponding re-transmits) that cause the poor performance. To work-around this issue, significantly increase the IPG in the MAC to allow enough gap for the link partner to transmit and reduce the Rx latency in the analog PHY to 0 to reduce the number of collisions. Signed-off-by: Bruce Allan Tested-by: Jeff Pieper Signed-off-by: Jeff Kirsher --- Reading git-diff-tree failed