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Is it possible to view the time delta between each line?

Open lheinold opened this issue 3 years ago • 7 comments

Is your feature request related to a problem? Please describe. I know how to get the time delta from the beginning of the file or from a marked line (shift+t) but is there a way to show the delta between each line? So if messages were being printed every second (for example), the time delta would show 1s, 1s, 1s, 1s instead of 1s, 2s, 3s, 4s.

Describe the solution you'd like A way to switch from cumulative time delta to time delta from the previous line.

Describe alternatives you've considered While the current feature (shift+t) does show the same information, it is not as easy (for me) to understand.

Additional context N/A

lheinold avatar May 12 '22 13:05 lheinold

Can you explain what you're trying to do/how it would be used?

The data is not shown in the log view now, but it is available when querying the log tables with SQL as the log_idle_msecs column. Would that satisfy your ultimate use case?

tstack avatar May 12 '22 13:05 tstack

Basically, the software I'm debugging is going much slower than usual and log statements that are usually .001s apart or less are .02s+. I am trying to write up a description of the issue and want to be able to put something like "log statements are anywhere from x ms to y ms apart, averaging around z ms". I can get this information from the "shift+t" option and using a calculator but I am lazy (lol).

I have not really worked with the SQL log tables but it does sound like that could satisfy my use case. I'll look into it, thanks!

lheinold avatar May 12 '22 14:05 lheinold

This would be super useful for further derivations from the timestamps. Like, this log I usually see every 5 seconds, but starting at this time, I saw it only every 6 or 7 seconds..Could do a histogram on the distribution of the deltas of repeating log lines

haydenflinner avatar Aug 31 '22 01:08 haydenflinner

Deltas would be very useful! However, I was able to get something good enough for me with

lnav  -n \
        -c ';SELECT log_text from generic_log WHERE log_idle_msecs > 100' 
        -c ':write-raw-to -'  \
        my.log \
   | lnav

unhammer avatar Apr 25 '23 09:04 unhammer