From 7f2aea42cf8b8e959fde57bce9d4424ca9520a28 Mon Sep 17 00:00:00 2001 From: arybchik Date: Wed, 25 Mar 2015 10:25:45 +0000 Subject: MFC: 277895 sfxge: Separate software Tx queue limit for non-TCP traffic Add separate software Tx queue limit for non-TCP traffic to make total limit higher and avoid local drops of TCP packets because of no backpressure. There is no point to make non-TCP limit high since without backpressure UDP stream easily overflows any sensible limit. Split early drops statistics since it is better to have separate counter for each drop reason to make it unabmiguous. Add software Tx queue high watermark. The information is very useful to understand how big queues grow under traffic load. Sponsored by: Solarflare Communications, Inc. Approved by: gnn (mentor) --- share/man/man4/sfxge.4 | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) (limited to 'share') diff --git a/share/man/man4/sfxge.4 b/share/man/man4/sfxge.4 index b94a31a..9659629 100644 --- a/share/man/man4/sfxge.4 +++ b/share/man/man4/sfxge.4 @@ -93,10 +93,18 @@ Supported values are: 512, 1024, 2048 and 4096. .It Va hw.sfxge.tx_dpl_get_max The maximum length of the deferred packet .Dq get-list -for queued transmit -packets, used only if the transmit queue lock can be acquired. +for queued transmit packets (TCP and non-TCP), used only if the transmit +queue lock can be acquired. If a packet is dropped, the -.Va tx_early_drops +.Va tx_get_overflow +counter is incremented and the local sender receives ENOBUFS. +The value must be greater than 0. +.It Va hw.sfxge.tx_dpl_get_non_tcp_max +The maximum number of non-TCP packets in the deferred packet +.Dq get-list +, used only if the transmit queue lock can be acquired. +If packet is dropped, the +.Va tx_get_non_tcp_overflow counter is incremented and the local sender receives ENOBUFS. The value must be greater than 0. .It Va hw.sfxge.tx_dpl_put_max @@ -105,7 +113,7 @@ The maximum length of the deferred packet for queued transmit packets, used if the transmit queue lock cannot be acquired. If a packet is dropped, the -.Va tx_early_drops +.Va tx_put_overflow counter is incremented and the local sender receives ENOBUFS. The value must be greater than or equal to 0. .It Va hw.sfxge.N.max_rss_channels -- cgit v1.1