zpool's API has some kind of limitation on it. If you poll it too quickly it returns nothing. Thus, appearing down.
If my miner has just polled the API, and then I restart it, 9 times out of 10 the API return is blank. Yes, it's very annoying.
1 query every 10s is the limit.
2018-01-26 11:32:21,345 [ zpool][ pools][ ERROR] zpool API error. Attempt: 1/10. 'ValueError: No JSON object could be decoded'
2018-01-26 11:32:32,443 [ zpool][ pools][ ERROR] zpool API error. Attempt: 2/10. 'ValueError: No JSON object could be decoded'
2018-01-26 11:37:56,408 [ zpool][ pools][ DEBUG] Getting zpool data.
In this scenario, assuming you don't have multiple systems making similar API calls from the same IP, you're not necessarily experiencing the 10-second limit crackfoo described. Rather, this is likely due to the site being hammered overall, and not being able to keep up with the sheer volume of requests. Of course, the end result is still the same.