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So I got the following message from my server-administrator the other day:

Hi ****,

We hope you are doing well today.

We have noticed one of your accounts was running multiple cron jobs with 1 minute intervals. (Three; and I admit they could've been merge into 1. There were not 1000's of lines of code, literally no more than 35 combined)

-snip-

On a shared hosting server, running a cron job every minute can have an adverse impact on the server's health and other users on the same server. To prevent the server from being negatively affected, we have modified the cron jobs as below:

-snip-

They will now run every at the above specified intervals. Please do not run any cronjob that has less than 15 minute intervals.

Your cooperation will be much appreciated in this regard.

Should you have further questions or concerns, please update this ticket.

Best Regards, ****.

Does this make sense to anyone? Because I have looked to the cloudlinux documentation and it doesn't seem to make any sense:

Picture from cloudlinux documentation

Picture from cloudlinux documentation

I pay for a "semi-dedicated" server off them, and 80 available Entry Processes. The only way I see this being a problem is if they load more users onto servers where they don't have the actual resources to account for those said users and their plans, because this was his "example":

Unfortunately, we have to maintain some minimum restrictions to maintain the hosting quality. Imagine what might happen if 50 users run 150 cron jobs per minute on the server. A regular server might crawl.

And like I said, the only way I see that being a problem is if the users resources account for more than the server can handle.

Am I wrong to think this? I never got linked to documentation explaining his argument or anything, he just referred be to his "terms of service" and basically told me he works with it everyday and that I don't know what I am talking about.

Crimin4L
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1 Answers1

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CageFS documentation mentioning that the "user should not feel any way restricted" refers to file system and process isolation. A chroot or container. Users are not restricted in the applications and config files they install, but this does not imply anything about resource quotas.

Possibly the cron limitation is imposed by your host regardless of available capacity or your process quota. Easier to write a naïve crontab parser than doing good performance root cause analysis and capacity planning.

Read those terms of service, although almost certainly as administrators of the container host they are allowed to do this. They have a point that frequent cron jobs can be a significant load, especially in resource constrained environments. Although I wonder how enormous their oversubscription ratio is that even with a meagre quota of 100 processes they still feel the need to manage crontabs.

To make a distinction, you rented a container from a shared hosting provider, who uses CloudLinux Shared. Dedicated server use cases for CloudLinux exist, same as upstream RHEL or CL's own clone AlmaLinux.

John Mahowald
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