Module Name: src
Committed By: jdolecek
Date: Wed Apr 8 23:01:52 UTC 2020
Modified Files:
src/share/man/man4: wm.4
Log Message:
add a warning in checksum offload that hardware TCP segmentation might be
slow
on I219 I observe about 35% transmit performance drop when tso4 enabled
To generate a diff of this commit:
cvs rdiff -u -r1.40 -r1.41 src/share/man/man4/wm.4
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/share/man/man4/wm.4
diff -u src/share/man/man4/wm.4:1.40 src/share/man/man4/wm.4:1.41
--- src/share/man/man4/wm.4:1.40 Fri Apr 13 06:04:12 2018
+++ src/share/man/man4/wm.4 Wed Apr 8 23:01:51 2020
@@ -1,4 +1,4 @@
-.\" $NetBSD: wm.4,v 1.40 2018/04/13 06:04:12 msaitoh Exp $
+.\" $NetBSD: wm.4,v 1.41 2020/04/08 23:01:51 jdolecek Exp $
.\"
.\" Copyright 2002, 2003 Wasabi Systems, Inc.
.\" All rights reserved.
@@ -33,7 +33,7 @@
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
-.Dd April 13, 2018
+.Dd April 9, 2020
.Dt WM 4
.Os
.Sh NAME
@@ -167,6 +167,8 @@ in hardware.
The
.Nm
driver supports these features of the chip.
+At least for some chips (e.g. I219) hardware TCP segmentation is slow,
+and slows down transmit performance when turned on.
See
.Xr ifconfig 8
for information on how to enable this feature.
