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* Increasing dmesg buffer size?
@ 2001-10-01 23:46 Jordan Breeding
  2001-10-01 23:48 ` Randy.Dunlap
                   ` (3 more replies)
  0 siblings, 4 replies; 5+ messages in thread
From: Jordan Breeding @ 2001-10-01 23:46 UTC (permalink / raw)
  To: Linux Kernel

What kernel parameter do I need to modify in the source to allow a
larger dmesg buffer?  I have a lot of boot messages and I currently
loose about 10-20 lines immediately and they can not even be seen in
/var/log/dmesg because that file gets dumped after those lines are
already gone.  Thanks to anyone who can help.

Jordan Breeding

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Increasing dmesg buffer size?
  2001-10-01 23:46 Increasing dmesg buffer size? Jordan Breeding
@ 2001-10-01 23:48 ` Randy.Dunlap
  2001-10-01 23:50 ` Mike Fedyk
                   ` (2 subsequent siblings)
  3 siblings, 0 replies; 5+ messages in thread
From: Randy.Dunlap @ 2001-10-01 23:48 UTC (permalink / raw)
  To: Jordan Breeding; +Cc: Linux Kernel

Jordan Breeding wrote:
> 
> What kernel parameter do I need to modify in the source to allow a
> larger dmesg buffer?  I have a lot of boot messages and I currently
> loose about 10-20 lines immediately and they can not even be seen in
> /var/log/dmesg because that file gets dumped after those lines are
> already gone.  Thanks to anyone who can help.

That would be a #define of LOG_BUF_LEN in linux/kernel/printk.c.

Be sure to keep it a power of 2.

There have been several patch files for this on the kernel
mailing list, but it's easy enough to DIY.

~Randy

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Increasing dmesg buffer size?
  2001-10-01 23:46 Increasing dmesg buffer size? Jordan Breeding
  2001-10-01 23:48 ` Randy.Dunlap
@ 2001-10-01 23:50 ` Mike Fedyk
  2001-10-01 23:55 ` James Simmons
  2001-10-02  1:14 ` Tim Moore
  3 siblings, 0 replies; 5+ messages in thread
From: Mike Fedyk @ 2001-10-01 23:50 UTC (permalink / raw)
  To: Linux Kernel

On Mon, Oct 01, 2001 at 06:46:01PM -0500, Jordan Breeding wrote:
> What kernel parameter do I need to modify in the source to allow a
> larger dmesg buffer?  I have a lot of boot messages and I currently
> loose about 10-20 lines immediately and they can not even be seen in
> /var/log/dmesg because that file gets dumped after those lines are
> already gone.  Thanks to anyone who can help.
> 

Does dmesg wrap around before klogd can grab the info?  Check
/var/log/kern.log (in debian, your filename may vary...) to see...

Mike

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Increasing dmesg buffer size?
  2001-10-01 23:46 Increasing dmesg buffer size? Jordan Breeding
  2001-10-01 23:48 ` Randy.Dunlap
  2001-10-01 23:50 ` Mike Fedyk
@ 2001-10-01 23:55 ` James Simmons
  2001-10-02  1:14 ` Tim Moore
  3 siblings, 0 replies; 5+ messages in thread
From: James Simmons @ 2001-10-01 23:55 UTC (permalink / raw)
  To: Jordan Breeding; +Cc: Linux Kernel


> What kernel parameter do I need to modify in the source to allow a
> larger dmesg buffer?  I have a lot of boot messages and I currently
> loose about 10-20 lines immediately and they can not even be seen in
> /var/log/dmesg because that file gets dumped after those lines are
> already gone.  Thanks to anyone who can help.

No command line paramter. Go into linux/kernel/printk.c and increase the
value of LOG_BUF_LEN. It must be a power of two.


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Increasing dmesg buffer size?
  2001-10-01 23:46 Increasing dmesg buffer size? Jordan Breeding
                   ` (2 preceding siblings ...)
  2001-10-01 23:55 ` James Simmons
@ 2001-10-02  1:14 ` Tim Moore
  3 siblings, 0 replies; 5+ messages in thread
From: Tim Moore @ 2001-10-02  1:14 UTC (permalink / raw)
  To: Jordan Breeding; +Cc: Linux Kernel

Jordan Breeding wrote:
> 
> What kernel parameter do I need to modify in the source to allow a
> larger dmesg buffer?  I have a lot of boot messages and I currently

Note the -s flag.

rgds,
tim.

DMESG(8)                                                 DMESG(8)

NAME
       dmesg - print or control the kernel ring buffer

SYNOPSIS
       dmesg [ -c ] [ -n level ] [ -s bufsize ]


--

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2001-10-02  1:13 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
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2001-10-01 23:46 Increasing dmesg buffer size? Jordan Breeding
2001-10-01 23:48 ` Randy.Dunlap
2001-10-01 23:50 ` Mike Fedyk
2001-10-01 23:55 ` James Simmons
2001-10-02  1:14 ` Tim Moore

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