QNX Operating System/Discussion/OSTech/slog2info -w skips processes that are not running/List of Posts
 
Forum Topic - slog2info -w skips processes that are not running:
   
Update
david lavacek
02/24/2022 6:25 PM
post121738
slog2info -w skips processes that are not running   
slog2info prints information from the slogger buffer. By default, it prints only infomration from the buffer. Using the 
"-w" option, it should print information from the buffer and then keep printing new information that is slogged 
afterwards.

It has been observed that there is another difference in behiavior with the "-w" option. Processes which are not running
 at the time "slog2info -w" is called are skipped. Even though those processes are in the slogger buffer (having run to 
completion previously), even their history is ignored.

example sequence:
1. start system
2. run a process X which runs, slogs information, then terminates.
3. run "slog2info". Observe the slogs of process X along with everything else
4. run "slog2info -w". Observe that process X slogs do not show up.

Testing was done with QNX 7.0. Slog2info build info:
QNX_BUILDID=(GNU)9d193bf4a577498ee3cd4eb7fe291a8c
NAME=slog2info
DESCRIPTION=SLOGGER2 system service
DATE=2017/01/19-14:49:37-EST
STATE=stable
HOST=sdp700-node1
USER=builder
VERSION=7.0.0
TAGID=700-SDP_3_build-aarch64-8
Jack Nowinski
03/04/2022 9:27 AM
post121745
Re: slog2info -w skips processes that are not running   
The behavior that you describe is consistent with the original intent of the -w/-W (live log streaming feature).

slog2info [-w/-W] queries slogger2 to find out which buffer sets are still live.

Whereas slog2info alone performs a static log dump of everything under /dev/shmem/slogger2, which also includes (for a 
certain time) buffer sets from terminated processes.
david lavacek
03/04/2022 11:08 AM
post121746
Re: slog2info -w skips processes that are not running   
This behavior is not clear from the documentation. The option states that the -w option "prints all available older logs
". Skipping inactive processes means that all older logs are not printed.

More importantly, this makes review of all log data complicated. For test systems, we run slog2info with the -w option 
at startup. The intent is to see everything that happened during boot and then keep printing everything that comes later
. With early processes getting skipped, it is not clear how to achieve this without printing a lot of information twice 
(aka run slog2info then again with the -w option) or possibly missing some data (slog2 info, then with the -c option, 
then with the -w option.

Return