Performance indicators and performance specifications of block storage

Different types of block storage (such as cloud disks and local disks) have different performance metrics and performance specifications. Understanding and comprehensively considering performance indicators and capacity requirements can help you select block storage products that are suitable for specific workload and application requirements to meet your storage requirements. This article introduces the performance metrics and performance specifications of cloud disks and local disks.

performance index

The performance indicators of block storage products mainly include IOPS, throughput and access latency. Some block storage products also have requirements for capacity, for example, the capacity ranges of ESSD cloud disks of different performance levels are different.

IOPS（Input/Output Operations per Second）

IOPS refers to the number of I/Os that can be processed per second, indicating the ability of block storage to process read/write (output/input), and the unit is times. If you need to deploy transaction intensive applications, such as database applications and other typical scenarios, you need to pay attention to IOPS performance. Among them, the SSD cloud disk can obtain the expected IOPS performance only when it is attached to an I/O optimized instance. When attaching to an instance that is not I/O optimized, the SSD cloud disk cannot obtain the expected IOPS performance. How to check whether it belongs to an I/O optimization instance, see Instance Type Family 。 Common IOPS indicators include sequential operation and random operation, as shown in the following table.

index	describe	Data access mode
Total IOPS	Total number of I/O operations performed per second	Discontinuous and continuous access to hard disk storage locations
Random read IOPS	Average number of random read I/O operations performed per second	Discontinuous access to hard disk storage locations
Random write IOPS	Average number of random write I/O operations performed per second	Discontinuous access to hard disk storage locations
Sequential read IOPS	The average number of sequential read I/O operations performed per second	Continuous access to hard disk storage locations
Write IOPS sequentially	The average number of sequential write I/O operations performed per second	Continuous access to hard disk storage locations

Throughput
Throughput refers to the number of data that can be successfully transmitted per unit time, in MB/s. If you need to deploy a large number of sequential read/write applications, such as typical scenarios such as Hadoop offline computing business, you need to focus on throughput.
Latency
Access delay refers to the time required for block storage to process an I/O, in seconds, milliseconds or μ s. Excessive delay will lead to application performance degradation or error reporting.
- If your application is sensitive to high latency, such as database applications, it is recommended that you use ESSD AutoPL cloud disk, ESSD cloud disk, SSD cloud disk or local SSD disk products.
- If your application focuses on data throughput and is relatively insensitive to latency, such as Hadoop offline computing and other throughput intensive applications, it is recommended that you use SATA HDD local disk products included in d1 or d1ne big data instance types.
Capacity
Capacity refers to the size of storage space, in units of TiB, GiB, MiB or KiB. The block storage capacity is calculated in binary units, representing the data size of 1024 carry, for example, 1 GiB=1024 MiB.
Capacity is not a measure of the performance of block storage products, but for storage devices, different capacities can achieve different performance. The larger the capacity, the stronger the data processing capability of the storage device. The I/O performance per unit capacity of the same type of block storage products is the same, but the cloud disk performance increases linearly with the capacity growth until it reaches the upper limit of the single disk performance of this type of block storage. The ESSD cloud disk can also select different performance levels in different capacity ranges.

Test the performance of different block storage types, see Test block storage performance 、 Test the performance of ESSD cloud disk IOPS 、 Test the performance of ESSD PL-X cloud disk and Test the local disk performance of the i4p instance 。

Cloud Disk Performance

The performance comparison of various cloud disks is shown in the following table.

explain

SSD cloud disk, efficient cloud disk and ordinary cloud disk belong to the previous generation cloud disk products, and have stopped selling in some regions and availability zones. When you select cloud disks, it is recommended to replace efficient cloud disks and ordinary cloud disks with ESSD PL0 cloud disks or ESSD Entry cloud disks, and replace SSD cloud disks with ESSD AutoPL cloud disks.

Performance category	ESSD AutoPL cloud disk	ESSD PL-X cloud disk (invited test)	ESSD cloud disk				ESSD Entry Cloud Disk	SSD cloud disk	Efficient cloud disk	Ordinary cloud disk
Performance Level	The capacity and performance are decoupled, and the benchmark performance is equal to the ESSD PL1. You can purchase additional preconfigured performance and enable performance bursts	PL-X	PL3	PL2	PL1	PL0	nothing	nothing	nothing	nothing
Single disk capacity range (GiB)	1~65,536	40~32,768	1,261~65,536	461~65,536	20~65,536	1~65,536	10~32,768	20~32,768	20~32,768	5~2,000
Maximum/minimum IOPS	1,000,000/3,000	3,000,000/100	1,000,000/64,850	100,000/24,872	50,000/2,800	10,000/1,812	6,000/1,880	25,000/2,400^②	5,000/1,960	hundreds
Maximum/minimum throughput (MB/s)	4,096/125	12,288/0.39	4,000/750.5	750/350.5	350/130	180/100	150/101.5	300/130^②	140/103	30~40
Single disk IOPS performance calculation formula^①	Benchmark performance: Max {min {1800+50 * capacity, 50000}, 3000} Pre configured performance: Min {preconfigured IOPS, 50000} Performance burst: Min {instance type, 1000000}	Preconfigured IOPS	Min {1800+50 * capacity, 1000000}	Min {1800+50 * capacity, 100000}	Min {1800+50 * capacity, 50000}	Min {1800+12 * capacity, 10000}	Min {1800+8 * capacity, 6000}	Min {1800+30 * capacity, 25000}	Min {1800+8 * capacity, 5000}	nothing
Single disk throughput performance calculation formula (MB/s)^①	Benchmark performance: Max {min {120+0.5 * capacity, 350}, 125} Pre configured performance: Min {16 KB * Pre configured IOPS/1024, maximum throughput of a single disk} Performance burst: Min {Instance type, 4 GB/s}	Min {4 KB * Pre configured additional IOPS/1024, 12288}	Min {120+0.5 * capacity, 4000}	Min {120+0.5 * capacity, 750}	Min {120+0.5 * capacity, 350}	Min {100+0.25 * capacity, 180}	Min {100+0.15 * capacity, 150}	Min {120+0.5 * capacity, 300}	Min {100+0.15 * capacity, 140}	nothing
Data reliability	99.9999999%	99.9999999%	99.9999999%	99.9999999%	99.9999999%	99.9999999%	99.9999999%	99.9999999%	99.9999999%	99.9999999%
Average delay of one-way random write (ms), Block Size=4K	zero point two	zero point zero three	zero point two	zero point two	zero point two	0.3~0.5	1~3	0.5~2	1~3	5~10

^① Description of single disk performance calculation formula:
- Take the calculation formula for the maximum IOPS of a single ESS PL0 cloud disk as an example: starting at 1800, each GiB increases by 12, and the upper limit is 10000.
- Take the calculation formula for the maximum throughput of a single ESSD PL0 cloud disk as an example: when starting at 100 MB/s, 0.25 MB/s will be added per GiB, and the upper limit is 180 MB/s.
^② The performance of the SSD cloud disk varies according to the size of the data block. The smaller the data block, the smaller the throughput, and the higher the IOPS, as shown in the following table.
Block size (KiB)
Maximum IOPS
Throughput (MB/s)
four
About 25000
About 100
sixteen
About 17200
About 260
thirty-two
About 9600
About 300
sixty-four
About 4800
About 300

Local disk performance

NVMe SSD local disk

The NVMe SSD local disk performance of the big data instance type family d3c is shown in the following table.

index	Single disk performance	ecs.d3c.3xlarge	ecs.d3c.7xlarge	ecs.d3c.14xlarge
Maximum read IOPS	100,000	100,000	200,000	400,000
Maximum read throughput	4 GB/s	4 GB/s	8 GB/s	16 GB/s
Maximum write throughput	2 GB/s	2 GB/s	4 GB/s	8 GB/s

The NVMe SSD local disk performance of the local SSD instance type family i4 is shown in the following table.

NVMe SSD Metrics	ecs.i4.large	ecs.i4.xlarge	ecs.i4.2xlarge	ecs.i4.4xlarge	ecs.i4.8xlarge	ecs.i4.16xlarge	ecs.i4.32xlarge
Maximum read IOPS	112 thousand and 500	225 thousand	450 thousand	900 thousand	1 million 800 thousand	3 million 600 thousand	7 million 200 thousand
Maximum read throughput	0.75 GB/s	1.5 GB/s	3 GB/s	6 GB/s	12 GB/s	24 GB/s	48 GB/s
Maximum write throughput	0.375 GB/s	0.75 GB/s	1.5 GB/s	3 GB/s	6 GB/s	12 GB/s	24 GB/s

explain

The indicators in the table are the best performance. It is recommended that you use the latest version of Linux images (this instance type family only supports Linux images) to get the best performance, for example Alibaba Cloud Linux 3 。

The NVMe SSD local disk performance of the local SSD instance type family i4g and i4r is shown in the following table.

NVMe SSD Metrics	Ecs.i4g.4xlarge and ecs.i4r.4xlarge	Ecs.i4g.8xlarge and ecs.i4r.8xlarge	Ecs.i4g.16xlarge and ecs.i4r.16xlarge	Ecs.i4g.32xlarge and ecs.i4r.32xlarge
Maximum read IOPS	250 thousand	500 thousand	1 million	2 million
Maximum read throughput	1.5 GB/s	3 GB/s	6 GB/s	12 GB/s
Maximum write throughput	1 GB/s	2 GB/s	4 GB/s	8 GB/s

explain

The NVMe SSD local disk performance of the local SSD instance type family i3 is shown in the following table.

NVMe SSD Metrics	ecs.i3.xlarge	ecs.i3.2xlarge	ecs.i3.4xlarge	ecs.i3.8xlarge	ecs.i3.13xlarge	ecs.i3.26xlarge
Maximum read IOPS	250 thousand	500 thousand	1 million	2 million	3 million	6 million
Maximum read throughput	1.5 GB/s	3 GB/s	6 GB/s	12 GB/s	18 GB/s	36 GB/s
Maximum write throughput	1 GB/s	2 GB/s	4 GB/s	8 GB/s	12 GB/s	24 GB/s

explain

The NVMe SSD local disk performance of the local SSD instance type family i3g is shown in the following table.

NVMe SSD Metrics	ecs.i3g.2xlarge	ecs.i3g.4xlarge	ecs.i3g.8xlarge	ecs.i3g.13xlarge	ecs.i3g.26xlarge
Maximum read IOPS	125 thousand	250 thousand	500 thousand	750 thousand	1 million 500 thousand
Maximum read throughput	0.75 GB/s	1.5 GB/s	3 GB/s	4.5 GB/s	9 GB/s
Maximum write throughput	0.5 GB/s	1 GB/s	2 GB/s	3 GB/s	6 GB/s

explain

The NVMe SSD local disk performance of the local SSD instance type family i2 and i2g is shown in the following table.

NVMe SSD Metrics	Single disk performance		Comprehensive instance performance^①
NVMe SSD Metrics	Only ecs.i2.xlarge and ecs.i2g.2xlarge	Other i2 and i2g specifications	Comprehensive instance performance^①
Maximum capacity	894 GiB	1,788 GiB	8*1,788 GiB
Maximum read IOPS	150 thousand	300 thousand	1 million 500 thousand
Maximum read throughput	1 GB/s	2 GB/s	16 GB/s
Maximum write throughput	0.5 GB/s	1 GB/s	8 GB/s
access delay	Microsecond (μ s)

^① The comprehensive instance performance is only applicable to ecs.i2.16xlarge, which represents the local storage performance of the largest specification in the i2 specification family.

The NVMe SSD local disk performance of the local SSD instance type family i2ne and i2gne is shown in the following table.

NVMe SSD Metrics	Ecs.i2ne.xlarge and ecs.i2gne.2xlarge	Ecs.i2ne.2xlarge and ecs.i2gne.4xlarge	Ecs.i2ne.4xlarge and ecs.i2gne.8xlarge	Ecs.i2ne.8xlarge and ecs.i2gne.16xlarge	ecs.i2ne.16xlarge
Maximum capacity	894 GiB	1,788 GiB	2*1,788 GiB	4*1,788 GiB	8*1,788 GiB
Maximum read IOPS	250 thousand	500 thousand	1 million	2 million	4 million
Maximum read throughput	1.5 GB/s	3 GB/s	6 GB/s	12 GB/s	24 GB/s
Maximum write throughput	1 GB/s	2 GB/s	4 GB/s	8 GB/s	16 GB/s
access delay	Microsecond (μ s)

The NVMe SSD local disk performance of the local SSD instance type family i1 is shown in the following table.

NVMe SSD Metrics	Single disk performance	Comprehensive instance performance^②
Maximum capacity	1,456 GiB	2,912 GiB
Maximum IOPS	240 thousand	480 thousand
Write IOPS^①	Min {165 * capacity, 240000}	2 * min {165 * capacity, 240000}
Read IOPS^①	Min {165 * capacity, 240000}	2 * min {165 * capacity, 240000}
Maximum read throughput	2 GB/s	4 GB/s
Read Throughput^①	Min {1.4 * capacity, 2000} MB/s	2 * min {1.4 * capacity, 2000} MB/s
Maximum write throughput	1.2 GB/s	2.4 GB/s
Write Throughput^①	Min {0.85 * capacity, 1200} MB/s	2 * min {0.85 * capacity, 1200} MB/s
access delay	Microsecond (μ s)

^① Description of single disk performance calculation formula:

The formula for calculating IOPS written to a local disk of a single NVMe SSD is 165 IOPS per GiB, with a maximum of 240000 IOPS.
The formula for calculating the write throughput of a single NVMe SSD local disk is 0.85 MB/s per GiB, up to 1200 MB/s.

^② The comprehensive instance performance is only applicable to ecs.i1.14xlarge, which represents the local storage performance of the largest specification in the i1 specification family.

SATA HDD local disk

SATA HDD local disk performance is shown in the following table.

SATA HDD indicators	d1、d1ne		d2c		d2s		d3s
SATA HDD indicators	Single disk performance	Comprehensive instance performance	Single disk performance	Comprehensive instance performance	Single disk performance	Comprehensive instance performance	Single disk performance	Comprehensive instance performance
Maximum capacity	5,500 GiB	154,000 GiB	3,700 GiB	44,400 GiB	7,300 GiB	219,000 GiB	11,100 GiB	355,200 GiB
Maximum throughput	190 MB/s	5,320 MB/s	190 MB/s	2,280 MB/s	190 MB/s	5,700 MB/s	260 MB/s	8,320 MB/s
access delay	Milliseconds

explain

The comprehensive instance performance is only applicable to the ecs.d1.14xlarge, ecs.d1ne.14xlarge, ecs.d2c.24xlarge, ecs.d2s.20xlarge, ecs.d3s.16xlarge specifications, representing the local storage performance of the largest specification in each specification family.

Block size (KiB)	Maximum IOPS	Throughput (MB/s)
four	About 25000	About 100
sixteen	About 17200	About 260
thirty-two	About 9600	About 300
sixty-four	About 4800	About 300