Subject: Re: bin/28492 (more(1) doesn't handle NUL data blocks well)
To: None <tron@NetBSD.org, gnats-admin@netbsd.org, netbsd-bugs@netbsd.org,>
From: Matthias Scheler <tron@NetBSD.org>
List: netbsd-bugs
Date: 09/25/2006 21:20:03
The following reply was made to PR bin/28492; it has been noted by GNATS.

From: Matthias Scheler <tron@NetBSD.org>
To: Bob Kemp <bsd@allegory.demon.co.uk>
Cc: gnats-bugs@NetBSD.org
Subject: Re: bin/28492 (more(1) doesn't handle NUL data blocks well)
Date: Mon, 25 Sep 2006 22:19:33 +0100

 On Sun, Sep 24, 2006 at 08:08:14PM +0100, Bob Kemp wrote:
 > I'm running a fairly recent version of -current but it still happens.
 > 
 > $ uname -a
 > NetBSD tenebres.loc 3.99.21 NetBSD 3.99.21 (TENEBRES) #0: Sat Jul  1 17:11:20 BST 2006  rob@tenebres.loc:/altroot/sys/arch/i386/compile/TENEBRES i386
 
 Well, I wouldn't call that recent.
 
 > $ ps lp 6995
 >  UID  PID  PPID  CPU PRI NI     VSZ    RSS WCHAN   STAT TTY      TIME COMMAND
 >  1000 6995 14770 1858  -5  0 1048724 416820 biowait D+   ttyp2 0:07.90 more /dev/zero 
 > 
 > $ ps up 6995
 >  USER  PID %CPU %MEM     VSZ    RSS TTY   STAT STARTED    TIME COMMAND
 >  rob  6995  0.6 79.7 1048724 417372 ttyp2 D+    7:43PM 0:07.94 more /dev/zero 
 > 
 > 
 > Since I use Java, the memory limits are set higher and the box only has 512M.
 > If you have more memory, it might not feel so bad to you.
 [...]
 > $ ulimit -a
 > time(cpu-seconds)    unlimited
 > file(blocks)         unlimited
 > coredump(blocks)     unlimited
 > data(kbytes)         3145728		<---
 > stack(kbytes)        2048
 > lockedmem(kbytes)    169933
 > memory(kbytes)       509800
 > nofiles(descriptors) 500
 > processes            160
 > sbsize(bytes)        unlimited
 
 [...]
 
 Your datasize exceeds the hard limit of my box:
 
 $ ulimit -a
 time(seconds)        unlimited
 file(blocks)         unlimited
 data(kbytes)         131072		<---
 stack(kbytes)        2048
 coredump(blocks)     0
 memory(kbytes)       2045980
 locked memory(kbytes) 681994
 process(processes)   160
 nofiles(descriptors) 64
 sbsize(bytes)        unlimited
 
 > If you want more info, or for me to try something, just let me know.
 
 Can you please provide your kernel configuration and more importantly
 try with a standard kernel configuration? It looks to me like you
 extended certain limits above a save boundary.
 
 And could please also try to run "more" on a very large (e.g. 4GB) file?
 I bet your problem has nothing to do with a file full of zeros but
 with the VM limits and the large amount of input data.
 
 	Kind regards
 
 -- 
 Matthias Scheler                                  http://zhadum.org.uk/