strange scsi/CAM related dmesg output
avg at icyb.net.ua
Fri Jun 18 17:28:52 UTC 2010
on 18/06/2010 18:18 mdf at FreeBSD.org said the following:
> On Fri, Jun 18, 2010 at 8:11 AM, Alexander Best
> <alexbestms at uni-muenster.de> wrote:
>> On Mon, Jun 7, 2010 at 3:57 PM, John Baldwin <jhb at freebsd.org> wrote:
>>> It can happen because the print buffer size thing is not line-buffered, it is
>>> printf-invocation buffered.
>> hmmm...can this somehow be fixed? i'm not sure this is specific to
>> scsi/cam. the other day i bootd my system and almost all of the dmesg
>> output was displayed incorrectly. would increasing PRINTF_BUFR_SIZE
>> from 128 to lets say 512 or 1024 solve the issue?
> I think what jhb meant was that we could look for the '\n' and flush
> to console there, instead of waiting for the end of the buffer. This
> would perhaps have more interleaved full lines, but likely fewer
> interleaved partial lines.
Not sure if it's relevant here, but want to point out that writing to kernel
msgbuf is char-by-char, so any kind of interleaving is possible there and
PRINTF_BUFR_SIZE is irrelevant to that.
More information about the freebsd-current