Subject: CVS commit: src
To: None <>
From: Bill Sommerfeld <>
List: source-changes
Date: 02/07/1999 23:05:52
Module Name:	src
Committed By:	sommerfeld
Date:		Mon Feb  8 07:05:51 UTC 1999

Modified Files:
	src/sys/dev/wscons: wsdisplay.c
Log Message:
Change WSDISPLAYBURST from OBUFSIZ-1 to OBUFSIZ*4, for a ~15x
improvement in the "cat /usr/share/misc/termcap" benchmark on 486/75

ttwrite queues data for us in OBUFSIZ chunks.  If we only consume
OBUFSIZ-1 bytes per call to wsdisplaystart(), we're *guaranteed* to
fall behind when given maximum-sized reads (which will defer
processing the leftovers until ttrstrt gets called, after a timeout)

Note that OBUFSIZ*4 may be overkill; OBUFSIZ*3 may be sufficient to
get maximal performance; OBUFSIZ*2 resulted in only about a 2.5x
performance improvement, but it's 2am and I've done enough tweaking
for the night.