Open Telekom Cloud 2020 - FIO IOPS

Go back to list


Block storage performance is a crucial metric for any infrastructures storing large amount of structured data. Most of the databases stored on volume are mainly limited by the number of I/O per second the device can achieve in read and write mode.

To collect IOPS, Cloud Mercato makes usage of Flexible I/O Tester (FIO) with a configuration designed to highlight the IOPS value:

  • Block size: Small size of 4KB essentially stressing block handling not bandwidth
  • Access: Read and write not mixed
  • Mode: Random avoiding computable optimisation
  • No file system: Only infrastructure performance are relevant
  • Miscellaneous: We avoid most as possible buffers and cache

Above VM performance, Cloud providers also apply various methods to throttle IOPS depending:

  • AWS General Purpose SSD:
    • IOPS are directly linked to volume's size
    • Performance are burstable and won't be at their maximum 100% of the time
  • Google Persistent SSD:
    • IOPS are directly linked to volume's size
  • Azure No cache Premium LRS:
    • IOPS are directly linked to the the sum of all volumes' size owned by tenant
    • Performance depends of VM flavor
    • No cache option has been used