CloudWatch Monitoring free disk space on a tempdb for EC2 instance using Instance Store partitioned as ephemeral drives

Hi Andrew,

It appears there was a mix-up between EBS volumes and Instance Stores, which are actually distinct types of AWS storage as you might already know. Please let me know if I misunderstood it.

Coming back to the question again, The CloudWatch Agent can collect the metrics like Disk Reads/sec, Disk Writes/sec, Disk Read Bytes/sec, Disk Write Bytes/sec, % Disk Time, and metrics related to free disk space such as "Free Megabytes" or "% Free Space" on Windows servers. These metrics are standard for Windows Performance Monitor and can be configured for collection by the CloudWatch Agent through its configuration file. I think following metrics are important in order to monitor the disc for tempdb:

• Disk Reads/sec and Disk Writes/sec: To gauge the I/O throughput, important for understanding how frequently data is being read from or written to the tempdb.
• Disk Read Bytes/sec and Disk Write Bytes/sec: Measure the volume of data transferred, which helps in assessing the workload handled by the tempdb.
• % Disk Time: Indicates the percentage of time the disk is active, providing insight into disk utilization.
• Current Disk Queue Length: Shows the number of pending disk operations, useful for identifying bottlenecks.
• Free Megabytes or % Free Space: Essential for monitoring available disk space to ensure tempdb has sufficient room to operate efficiently.

Hope this helps.