System projections, can we disable some

EventStoreDB V5.X
1

System projections use quite a lot of disk and system resources. We only need two of them for our application. Is there no way of disabling some?
We now use:
RunProjections: All
StartStandardProjections: True

And stop two of them.

2

You can stop over http. Or not start all, and enable the ones you need…

3

Yeah thats what i thought. But when the cluster node restarts they are all back.

4

We don’t autostart (StartStandardProjection not set), and have an application level health check ensure the required one is running and healthy.

5

So if one is down you start it? We could have a check to see if its stopped and start it. Check that every 10s. Thats not a bad idea.

6

We set StartStandardProjection, then stop some projections. The are many time a node commits suicide and restarts itself, and the projection starts again. We have just encountered that issue, and the projection it started is the $by_correlation_id, which process all events from beginning. So can we have some settings that can disable some standard projections, and remain unchanged after restart ?

7

@idar.borlaug, @ndangthieu, which version are you using? If v5, then there is a known bug, that may cause projection to restart.

To disable system projection it should be enough to set START STANDARD PROJECTIONS setting to false.

8

We solved it in v5 with disabling system projections and having a cron job starting the two we wanted.

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