Open dmke opened 2 months ago
In lib/init.rb
, I have stumbled upon IRB.set_measure_callback
. The following configuration seems to do the trick:
# ~/.irbrc
IRB.conf[:MEASURE] = true
IRB.set_measure_callback do |context, code, line_no, &block|
trunc = code.strip.then { _1[...16] + (_1.size > 16 ? "..." : "") }
now = Time.now.strftime "%H:%S"
Process.setproctitle "irb:#{line_no} - running `#{trunc}` since #{now}"
block.()
now = Time.now.strftime "%H:%S"
Process.setproctitle "irb:#{line_no} - idle since #{now}"
end
I'm not sure what side effects to expect with IRB.conf[:MEASURE]
, so I'm leaving this issue open for further discussion.
I think there is a negative impact of overriding proc title.
If we do it, meaningfull proc name like ruby script_name.rb
my_awsome_rails_app_console
will be overrided.
I think this should be done in .irbrc
or in application code, not by default.
However, there are no pre/post evaluation hooks. Perhaps we can add more hooks.
I agree on your point regarding other uses of scripts leveraging the process title.
Come to think of it, there's also a potential security problem, when the code
block argument is something like pw = "supersecret\n"
, even if evaluating that may only take a few CPU cycles before the process title is changed back to "idle".
However, having a callback to run things around a command evaluation would be very valuable for this use case.
Description
Colleagues of mine regularly SSH into our servers, start an IRB session to look something up, and forget to logout. When they store database query results in local variables, they obviously occupy memory and can't be garbage collected.
It has happened on more than one occasion that I need to manually free resources because half a dozen IRB sessions have multiple GB of memory allocated. I would like to avoid currently active sessions though (i.e. where a user is actively collecting information).
As far as I can tell, I have no information what an IRB process is currently doing. I can't rely on CPU usage, as swapping may induce some load (on Ubuntu 24.04, I have noticed an otherwise idle IRB process to use up to 1% of CPU in
top
).It would be useful if IRB would update the process title (
Process.setproctitle
) to something meaningful, for example:Maybe this is achievable through a piece of code in
.irbrc
, but I haven't figured out how to do that.Result of irb_info
This is Ruby/IRB from Ubuntu 24.04 packages.
Terminal Emulator
Tilix on the workstation. This should not matter
Setting Files
Are you using
~/.irbrc
and~/.inputrc
?~/.irbrc
includes only commented# IRB.conf[:USE_MULTILINE] = false