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This limit is always sufficient to copy big files to a flash drive formatted in any of common filesystems. One opened block receives metadata and another receives data, then it just moves on. But if you start doing random writes you stop hitting the opened blocks and this is where lags come in.
== Bonus: Micron vSAN reference architecture ==
* 384 GB RAM 2667 MHz
* 2X Micron 5100 MAX 960 GB (randread: 93k iops, randwrite: 74k iops)
* 8X Micron 5200 ECO 3.84TB (randread: 95k iops, randwrite: 17k iops)
* 2x Xeon Gold 6142 (16c 2.6GHz)
* Mellanox ConnectX-4 Lx
* Mellanox SN2410 25GbE switches
«Aligns with VMWare AF-6, aims up to 50K iops per node»
* 1 replica
* 4 nodes
* 4 VMs on each node
* 8 vmdk per VM
* 4 threads per vmdk
Total parallelism: 512
100 %/70%/50%/30%/0% write
* «Baseline» (fits in cache): 121k/178k/249k/314k/486k iops
* «Capacity» (doesn’t): 51k/66k/90k/134k/363k
Conclusion:
* ~3800 write iops per drive
* ~11343 read iops per drive
* ~1600 write iops per drive when not in cache
Hyperconverged, though.
== Good SSD models ==
