With cloud network-based storage like EBS or pd-ssd, I doubt you will notice any IOPS-related perf penalty when running a RDBMS on top of ZFS. Assuming a mixed

With cloud network-based storage like EBS or pd-ssd, I doubt you will notice any IOPS-related perf penalty when running a RDBMS on top of ZFS. Assuming a mixed read/write workload, you will likely hit the disk write throughput limit first, as ZFS just writes ... a lot more, due to how blocks are stored internally: https://github.com/openzfs/zfs/issues/6584#issuecomment-384805998 https://github.com/openzfs/zfs/issues/6584#issuecomment-3848... On an innodb database, I get about 3x compress ratio with ZSTD compression, and ZFS still has to write about 2x more than EXT4.