Launch mountpoint in host systemd #29
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| return l.ActiveState != r.ActiveState | ||
| } | ||
| filter := func(name string) bool { return !strings.Contains(name, serviceName) } | ||
| updates, errChan := systemdConn.SubscribeUnitsCustom(50*time.Millisecond, 10, isChanged, filter) |
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so this spawns a goroutine with a seemingly endless loop: https://github.com/coreos/go-systemd/blob/main/dbus/subscription.go#L112
have you checked if those goroutines are terminated? should we defer close(updates) / defer close(errChan) for that?
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Unfortunately this leaks a goroutine and the two channels and I don't see a way around that. That goroutine writes to the channels, so I can't just defer close them or we'll get a panic and crash. Let me know if I'm missing something. The workaround is probably to just call ListUnits in my own polling function.
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yeah, neither do I see a better than implementing our polling function with a proper termination interface
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im ok with fixing it separately, as the bug is not confirmed (I can take that next week); but for now it seems that SubscribeUnitsCustom goroutines will always be left waiting on errChan <- err call (so at least consuming some memory, probably not CPU cycles)
This changes the mountpoint process to run within the host's systemd instead of within the CSI node container. This allows upgrades of the CSI driver without interrupting customer workloads.
This changes the mountpoint process to run within the host's systemd instead of within the CSI node container. This allows upgrades of the CSI driver without interrupting customer workloads.
To talk to systemd, the container mounts the host dbus socket and uses the dbus api via the
github.com/coreos/go-systemd/v22library (Apache licensed).