Alibaba Cloud Enterprise SSDs (ESSDs) use 25 Gigabit Ethernet and remote direct memory access (RDMA) to reduce latency and deliver up to 1,000,000 random read/write IOPS per disk. This topic describes the performance levels (PLs), scenarios, and maximum performance of ESSDs. This topic also provides reference information about each ESSD PL.
Specifications
The API parameter value cloud_essd indicates ESSDs. ESSDs are classified into four PLs based on the maximum performance per disk.
ESSD attribute | PL | |||
PL3 | PL2 | PL1 | PL0 | |
Performance description | Ultra-high maximum concurrent I/O performance and ultra-low I/O latency | High maximum concurrent I/O performance and low I/O latency | Moderate maximum concurrent I/O performance and low I/O latency | Moderate maximum concurrent I/O performance and low I/O latency |
Cloud disk capacity range (GB) | 1,265 to 64,000 | 465 to 64,000 | 20 to 64,000 | 20 to 64,000 |
Data reliability | 99.9999999% | 99.9999999% | 99.9999999% | 99.9999999% |
Maximum IOPS per disk | 1,000,000 | 100,000 | 50,000 | 10,000 |
Maximum throughput per disk (MB/s) | 4,000 | 750 | 350 | 180 |
Formula for calculating the IOPS per disk | min{1,800 + 50 × Capacity, 1,000,000} | min{1,800 + 50 × Capacity, 100,000} | min{1,800 + 50 × Capacity, 50,000} | min{1,800 + 12 × Capacity, 10,000} |
Formula for calculating the throughput per disk (MB/s) | min{120 + 0.5 × Capacity, 4,000} | min{120 + 0.5 × Capacity, 750} | min{120 + 0.5 × Capacity, 350} | min{100 + 0.25 × Capacity, 180} |
Scenarios
ESSDs are suitable for latency-sensitive applications or I/O intensive business scenarios.
Relationship between the ESSD capacity range and PL
The performance of a storage device is closely related to the capacity of the device. A storage device that has a larger capacity provides higher data processing capabilities. All ESSDs have the same I/O performance per unit of capacity. However, the performance of ESSDs increases linearly with its capacity until the maximum performance per disk at the PL is reached.
performance level (PL) | ESSD capacity range (GB) | Maximum IOPS | Maximum throughput (MB/s) |
PL0 | 20 to 64,000 | 10,000 | 180 |
PL1 | 20 to 64,000 | 50,000 | 350 |
PL2 | 465 to 64,000 | 100,000 | 750 |
PL3 | 1,265 to 64,000 | 1,000,000 | 4,000 |