Add Alerts for DiskLimit and MemoryLimit reached

[edbyford]

@ansd commented on Wed May 19 2021

We currently have an alert for LowDiskWatermarkPredicted.

Let's add two more alerts:

1. Low Disk Watermark reached:
   rabbitmq_disk_space_available_bytes < 0 for more than 10 minutes
2. Memory limit reached: e.g. rabbitmq_resident_memory_limit_bytes - rabbitmq_process_resident_memory_bytes < 0 for more than 10m

[ablease]

Hi @ansd. Similar to 33 Should we still play this story? We have some questions:

What is the intention with this story
Giving the age of this request, is it still relavent?