Don't run cron.php for 14min but only 4

[marcelklehr]

Apparently cron.php runs for 14min but is called every 5 minutes.
Is there a reason for the discrepancy?

Original issue: nextcloud/recognize#335

[nickvergessen]

Is there a reason for the discrepancy?

Yes, on bigger instances it often happens that one execution in parallel is not enough, so we use this to run ~3 in parallel.

[nickvergessen]

This is intended

[marcelklehr]

I see. On smaller instances it can create high load, though. Wouldn't it be simpler to have the admin add additional entries in crontab if they want higher throughput?

[nickvergessen]

On smaller instances it can create high load, though

How so? if there are no jobs, nothing is being done?

[marcelklehr]

On smaller instances it can create high load, though
How so? if there are no jobs, nothing is being done?

I meant small as in a Raspberry Pi for example. People running nextcloud on there may not have the resources to run 3 cron jobs in parallel.

[juliushaertl]

Yes, on bigger instances it often happens that one execution in parallel is not enough, so we use this to run ~3 in parallel.

Shouldn't we rather recommend to setup multiple cron jobs then? That way admins stay in control on how many parallel processes are running and can adapt that to the available resources.

[kc9jud]

Alternatively, this "maximum number of simultaneous cron jobs" should be configurable.

[kc9jud]

Yes, on bigger instances it often happens that one execution in parallel is not enough, so we use this to run ~3 in parallel.

@nickvergessen On one end we have "resource-constrained systems which can only handle a single simultaneous execution". On the opposite end of the spectrum where there are "resource-rich systems with lots of available cores/parallelism" and "large instances where one execution is not enough". I don't think "cron.php takes longer than 5 minutes" actually gives you enough information to distinguish between the two scenarios, so some configuration flag (either in Nextcloud itself or via scheduling multiple cron jobs) is needed.