Log File Viewer for the Terminal

#1

Post by wiradikusuma » Tue, Mar 24, 2026, 5:32 AM UTC

Log File Viewer for the Terminal
lnav.org

Re: Log File Viewer for the Terminal

#2

Post by p0w3n3d » Tue, Mar 24, 2026, 6:21 AM UTC

This is almost the thing I want and need. What I need is some sort of TUI grafana - Json log splitter/organizer/finder

Re: Log File Viewer for the Terminal

#3

Post by asmosoinio » Tue, Mar 24, 2026, 6:27 AM UTC

Looks very useful, will give it a go.

This resonates with my use of grep+less: https://github.com/tstack/lnav?tab=readme-ov-file#why-not-ju...

Re: Log File Viewer for the Terminal

#4

Post by guessmyname » Tue, Mar 24, 2026, 6:30 AM UTC

Oh yeah! lnav is famous. I remember using it like a decade ago to monitor an array of web servers while at GoDaddy; good ol' times.

First commit is from Sep 13, 2009: https://github.com/tstack/lnav/commit/b4ec432515e95e86ec9d71... . Woah! we’re old.

This is what the UX looked like back in the day: https://github.com/tstack/lnav/commit/bce2caa654160518ec11f6...

Re: Log File Viewer for the Terminal

#5

Post by dima55 » Tue, Mar 24, 2026, 6:34 AM UTC

p0w3n3d wrote: post #2

This is almost the thing I want and need. What I need is some sort of TUI grafana - Json log splitter/organizer/finder

I use vnlog and feedgnuplot to massage and plot data on the console all the time. It's even less than a tui, but might be what you want.

Re: Log File Viewer for the Terminal

#6

Post by dloss » Tue, Mar 24, 2026, 7:23 AM UTC

dima55 wrote: post #5

p0w3n3d wrote: post #2

This is almost the thing I want and need. What I need is some sort of TUI grafana - Json log splitter/organizer/finder

I use vnlog and feedgnuplot to massage and plot data on the console all the time. It's even less than a tui, but might be what you want.

If you're fine with CLIs, maybe my Kelora project is worth a look. It's a very flexible log processor with built-in scripting: https://kelora.dev

Re: Log File Viewer for the Terminal

#7

Post by makapuf » Tue, Mar 24, 2026, 7:25 AM UTC

p0w3n3d wrote: post #2

This is almost the thing I want and need. What I need is some sort of TUI grafana - Json log splitter/organizer/finder

Currently working exactly on that https://gitlab.com/makapuf/treewalker (even if it could always use some love)

Re: Log File Viewer for the Terminal

#8

Post by steveharing1 » Tue, Mar 24, 2026, 7:53 AM UTC

I was looking for something like this, Appreciate it!

Re: Log File Viewer for the Terminal

#9

Post by brunosutic » Tue, Mar 24, 2026, 7:56 AM UTC

I tried lnav about 7-8 years ago and as a terminal junkie I really liked the features.

The only breaking thing was a huge (almost bloated) memory consumption. At that time lnav basically just kept everything in memory. Does anyone did that change?

Re: Log File Viewer for the Terminal

#10

Post by xx_ns » Tue, Mar 24, 2026, 8:14 AM UTC

brunosutic wrote: post #9

I tried lnav about 7-8 years ago and as a terminal junkie I really liked the features. The only breaking thing was a huge (almost bloated) memory consumption. At that time lnav basically just kept everything in memory. Does anyone did that change?

According to the linked homepage, the memory usage seems decent (few hundred megs for most use cases when working with a 3.3G logfile). There's a screenshot with various tasks and what the peak memory usage is.

At some point you need to keep quite a large context in memory to have both decent performance and useful features (that aren't unbearably slow to use). lnav seems to land at a reasonable middle ground.