Re: [PATCH/REQ] Increase kmsg buffer from 16K to 32K, kernel/printk.c

David Ford (
Sat, 27 Jan 2001 11:45:29 +0000

Ion Badulescu wrote:

> On Sat, 27 Jan 2001 08:01:14 +0000, David Ford <> wrote:
> > Does Linus or anyone object to raising the ksmg buffer from 16K to 32K?
> > 4/5 systems I have now overflow the buffer during boot before init is
> > even launched.
> Hmm, are you sure? man dmesg:
> [...]
> -sbufsize
> use a buffer of bufsize to query the kernel ring
> buffer. This is 8196 by default (this matches the
> default kernel syslog buffer size in 2.0.33 and
> 2.1.103). If you have set the kernel buffer to
> larger than the default then this option can be
> used to view the entire buffer.
> So try dmesg -s 16384. That's good enough for me on a 4-way SMP
> box with lots of SCSI on-board (and trust me, SMP generates a *huge*
> amount of kernel logging).

Well, as I said, the (current) 16K buffer is overflowed before init is
started. Being that I'd like to review the first page or two of boot
messages, I have to increase this limit all the time. The above man page
needs updated, the buffer size in 2.4.0 is 16K and it doesn't matter how
large you set the dmesg -s parameter, the kernel's buffer size is the most
you can retrieve from it.


  There is a natural aristocracy among men. The grounds of this are virtue and talents. Thomas Jefferson
  The good thing about standards is that there are so many to choose from. Andrew S. Tanenbaum

- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to Please read the FAQ at