mgedmin / memgraphinator

Graph the memory usage of a single process

memgraphinator

I want a tool to draw the memory usage graph of a given process over time. I want to see memory leaks.

I couldn't find one so I started writing my own.

Usage

./memgraphinator.py [--exit-when-process-dies]
./memgraphinator.py [--exit-when-process-dies] [-p|--pid] PID ...
./memgraphinator.py [--exit-when-process-dies] [--] command [args ...]
./memgraphinator.py -h|--help

positional arguments:

command [args] Command to execute and monitor

optional arguments:

-h, --help Show this help message and exit -p PID, --pid PID Specify existing process to monitor --exit-when-process-dies Exit when monitored process dies

Requirements

• Linux (for /proc/{pid}/status)
• Python
• PyGObject with GIR libraries for GTK etc.

Note

On Ubuntu be sure to apt-get install python3-gi python3-gi-cairo gir1.2-gtk-3

• A reasonably new GTK+ (3.10 is fine but 3.12 is preferred)

Future plans

• Accurate time axis (when you suspend laptop, graph stops, but this is not reflected in "N seconds ago" messages)
• Export graph to CSV

memgraphinator's Issues

27-hour long graph of a stopped process disappears on zoom

1. monitor gnome-shell for 27 hours
2. wait until an assertion failure in mutter makes it crash on monitor hotplug
3. observe: when zooming in beyond a certain level the graph disappears

when a process dies, the graph stops -- but it's unclear that it stopped

Maybe append a [terminated] or something to the command line? Change the graph color?

What do the 2 lines mean?

There are 2 graphs shown at once, they appear to follow each other, what do the 2 lines mean?

Not really an issue but an explanation should be added to the readme.

Idea: track PSS

In addition to RSS and VIRT it might be nice to track PSS (Proportional set size, like RSS except shared memory pages are divided by the number of processes that share them).

You can get it from /proc/$pid/smaps_rollup, on a line containing

Pss:                    nnn kB

(If smaps_rollup is not available, you'd have to read /proc/$pid/smaps itself and sum the Pss for every mapping. I'm not sure which kernel version added smaps_rollup.)

TypeError: Couldn't find foreign struct converter for 'cairo.Context'

memgraphinator does not work on Ubuntu 19.04.

More specifically, it works, but it cannot draw the graph itself. All I see is a white box and a bunch of these errors on the console:

TypeError: Couldn't find foreign struct converter for 'cairo.Context'

Feature request: Pause / Resume button

For debugging, I have inserted some cin.get() lines to stop program execution at a particular point.

It would be useful to have a "Pause/Continue" button so that the graph does not scroll off all the way to the left.

Alternatively a scroll bar on the x axis to scroll through the history of the data.

Really useful tool for quickly finding memory leaks by the way.

Time computation is incorrect

I had a script running for just under two hours, and when zoomed out, memgraphinator claimed I was looking at data points more than 3 hours in the past.

High CPU usage after a while

Leaving memgraphinator open for 20 hours (plotting gnome-shell's memory usage) makes it eat ~34% CPU all the time, unless you pause it (paused, it eats ~2.5% CPU).