So I've seen various conversations around SharePoint Online throttling and I have been told various things by various Microsoft Engineers/Support Professionals regarding workflow throttling and I wanted to see if others in the community could corroborate these findings:
There is an individual task limit of 5,000 tasks per workflow instance that is enforced
I have also however been told that there is a 5,000 workflow instance per site collection limit, and also that there is a 5,000 task per site collection limit. Hard to tell what is what.
I have been told that 5,000 workflow requests to the azure workflow manager will put your site on a 24 hour throttle and queue >5,0000 requests that will re-initiate after the 24 hour period is over. In general I can't seem to find any concrete guidance on overall task and or workflow instance volume on a site collection that should be taken into consideration.
More importantly I cannot seem to figure out how to become un-throttled once it occurs, with it sometimes taking days before workflow start times (i.e. they fail to start in a timely fashion) and workflow lengths (they take a long time to run once started) decrease.
Can anyone shed some wisdom?
I have also been looking for information on this topic. I have created a Nintex Workflow that creates 11 different calendar events in the Office 365 calendar of the user. It works, however, each calendar event takes almost exactly 30 minutes to complete, so the entire workflow takes ~7.5 hours to run. Why is this happening? I can't find anything in the Nintex documentation or forums about this.
I contacted Nintex support about this issue and they referred me to the following articles:
The gist of these appears to be that throttling is happening on the O365 side of things, so blame Microsoft. As well, throttling in O365 is unpredictable, because Microsoft is continually tuning the performance of its services in response to network conditions. They also say that, once you have been throttled, continued network requests will only "dig the hole deeper", so to speak, as MS automatically tapers resources given to throttled tenants that don't back off.
So, unfortunately, there is not a really detailed answer to this question. In general, it seems that two things are guaranteed to get you throttled: making thousands of requests in a very short time, or making a high volume of requests continuously for a long time.