Diagnosing Growing Main-Process Memory in io.Connect Desktop

io.Connect Desktop
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Problem

The main (Electron browser) process of the container grows steadily across a working day. Memory does not return to its earlier level, and the running apps are eventually terminated abruptly.

The growth is visible in the perf-log entries written to the container log. Worth checking:

  • memoryKB for the Main entry
  • external and heapUsed

Below are few checks you can do:

Check whether it is really the main process

Read perf-log for whether a figure is abnormal (see Diagnosing High Desktop CPU Usage): compare against the rolled logs, examine memoryKB per process and break the platform total down per app before investigating the platform itself. For log locations and rollover, see Understanding logs in io.Connect.

Take a heap snapshot of the main process

You can capture a heap snapshot of the main process from the container UI:

  1. Tray icon → Diagnostics → Take heap snapshot.
  2. Take one snapshot at startup and a second one once memory usage has grown. Comparing two snapshots is far more useful than reading one.
  3. Open the resulting file in Chrome DevTools → Memory tab to analyse it.

When you open a support ticket, the snapshot files can be attached to it for a better picture during investigation.

Clicking Take heap snapshot produces no dialog, no toast and no progress indicator. The snapshot is smply written in the user data folder for the current environment and region (confirmed in 9.10):

%LocalAppData%\interop.io\io.Connect Desktop\UserData\<ENV>-<REG>\<epoch-milliseconds>.heapsnapshot

In the old Glue42 Enterprise 3.20 the file is in a Tick42 folder under the user data path.

Attach Chrome DevTools

Heap snapshots are point-in-time. If you can reproduce the growth on a machine you control, attaching DevTools gives you a live view.

Main process (Node side)

  1. Pass --inspect=9229 as a command line argument to the container executable.
  2. In Chrome, open chrome://inspect/.
  3. Click “Open dedicated DevTools for Node”, then add a connection to localhost:9229.
  4. After closing the connection dialog, a remote target appears.
  5. Click “inspect” to open DevTools and investigate memory usage and heap snapshots.

App windows (renderer processes)

  1. Pass --remote-debugging-port=9229 as a command line argument to the container executable.
  2. Open chrome://inspect/ in Chrome.
  3. A list of all running applications appears.
  4. Click “inspect” on any target to debug memory usage or take heap snapshots for that renderer process.

Check also Developers > Debugging

Correlate with what changed

If an app was updated that may cause unexpected behaviour - track every tiny change, compare before/after performance and have an easy to revert plan. io.Insights can be used to easily compare performance after each update: A Complete Walkthrough of the Grafana Observability Dashboard