Compute optimized instances
Compute optimized instances are ideal for compute-bound applications that benefit from high-performance processors.
C5 and C5n instances
These instances are well suited for the following:
-
Batch processing workloads
-
Media transcoding
-
High-performance web servers
-
High-performance computing (HPC)
-
Scientific modeling
-
Dedicated gaming servers and ad serving engines
-
Machine learning inference and other compute-intensive applications
Bare metal instances, such as c5.metal
, provide your applications
with direct access to physical resources of the host server, such as processors and
memory.
C6i and C6id instances
These instances are ideal for running advanced, compute-intensive workloads, such as the following:
-
High-performance computing (HPC)
-
Batch processing
-
Ad serving
-
Video encoding
-
Distributed analytics
-
Highly scalable multiplayer gaming
C6in instances
These instances are well suited for compute-intensive workloads such as the following:
-
Distributed computing applications
-
Network virtual appliances
-
Data analytics
-
High Performance Computing (HPC)
-
CPU-based AI/ML
For more information, see Amazon EC2 C6i Instances
C7a instances
These instances are powered by 4th generation AMD EPYC processors and are ideal for running advanced, compute-intensive workloads, such as the following:
-
High-performance computing (HPC)
-
Batch processing
-
Ad serving
-
Video encoding
-
Gaming servers
-
Scientific modeling
-
Distributed analytics
For more information, see Amazon EC2 C7a instances
C7g and C7gd instances
These instances are powered by Amazon Graviton3 processors and are ideal for running advanced, compute-intensive workloads, such as the following:
-
High-performance computing (HPC)
-
Batch processing
-
Ad serving
-
Video encoding
-
Gaming servers
-
Scientific modeling
-
Distributed analytics
For more information, see Amazon EC2 C7g instances
C7gn instances
Featuring the new Amazon Nitro Cards, C7gn instances deliver the highest network bandwidth, and the best packet-processing performance for Graviton-based Amazon EC2 instances. C7gn instances offer up to 200 Gbps network bandwidth and up to 50 percent higher packet-processing performance compared to previous generation C6gn instances. C7gn instances are ideal for network-intensive workloads, including:
-
Network virtual appliance workloads
-
Data-intensive workloads, such as data analytics
-
CPU-based artificial intelligence and machine learning (AI/ML) inference workloads
For more information, see Amazon EC2 C7gn instances
C7i instances
C7i instances are ideal for running compute intensive workloads, such as batch processing, machine learning, high end gaming, ad serving, and video encoding.
For more information, see Amazon EC2 C7i instances
Hpc7g instances
Hpc7g instances are powered by Amazon Graviton3E processors and the next generation Amazon Nitro Card. They deliver 200 Gbps advanced networking with Elastic Fabric Adapter (EFA) for low latency and high network performance.
Hpc7g instances are ideal for running compute-intensive HPC applications that benefit from compute and memory bandwidth performance and low network latency, such as computational fluid dynamics, molecular dynamics, and weather simulations.
For more information, see Amazon EC2 Hpc7g instances
Hpc7a instances
These instances feature up to 300 Gbps networking bandwidth with Elastic Fabric Adapter (EFA) for low latency and high network performance with Message Passing Interface (MPI). They feature up to 192 CPU cores with up to 768 GB of system memory.
Hpc7a instances are ideal for running compute-intensive HPC applications, such as computational fluid dynamics, molecular dynamics, and weather simulations that benefit from large core counts per instance and low network latency.
For more information, see Amazon EC2 Hpc7a instances
Contents
Hardware specifications
The following is a summary of the hardware specifications for compute optimized instances. A virtual central processing unit (vCPU) represents a portion of the physical CPU assigned to a virtual machine (VM). For x86 instances, there are two vCPUs per core. For Graviton instances, there is one vCPU per core.
Instance type | Default vCPUs | Memory (GiB) |
---|---|---|
c1.medium | 2 | 1.70 |
c1.xlarge | 8 | 7.00 |
c3.large | 2 | 3.75 |
c3.xlarge | 4 | 7.50 |
c3.2xlarge | 8 | 15.00 |
c3.4xlarge | 16 | 30.00 |
c3.8xlarge | 32 | 60.00 |
c4.large | 2 | 3.75 |
c4.xlarge | 4 | 7.50 |
c4.2xlarge | 8 | 15.00 |
c4.4xlarge | 16 | 30.00 |
c4.8xlarge | 36 | 60.00 |
c5.large | 2 | 4.00 |
c5.xlarge | 4 | 8.00 |
c5.2xlarge | 8 | 16.00 |
c5.4xlarge | 16 | 32.00 |
c5.9xlarge | 36 | 72.00 |
c5.12xlarge | 48 | 96.00 |
c5.18xlarge | 72 | 144.00 |
c5.24xlarge | 96 | 192.00 |
c5.metal | 96 | 192.00 |
c5a.large | 2 | 4.00 |
c5a.xlarge | 4 | 8.00 |
c5a.2xlarge | 8 | 16.00 |
c5a.4xlarge | 16 | 32.00 |
c5a.8xlarge | 32 | 64.00 |
c5a.12xlarge | 48 | 96.00 |
c5a.16xlarge | 64 | 128.00 |
c5a.24xlarge | 96 | 192.00 |
c5ad.large | 2 | 4.00 |
c5ad.xlarge | 4 | 8.00 |
c5ad.2xlarge | 8 | 16.00 |
c5ad.4xlarge | 16 | 32.00 |
c5ad.8xlarge | 32 | 64.00 |
c5ad.12xlarge | 48 | 96.00 |
c5ad.16xlarge | 64 | 128.00 |
c5ad.24xlarge | 96 | 192.00 |
c5d.large | 2 | 4.00 |
c5d.xlarge | 4 | 8.00 |
c5d.2xlarge | 8 | 16.00 |
c5d.4xlarge | 16 | 32.00 |
c5d.9xlarge | 36 | 72.00 |
c5d.12xlarge | 48 | 96.00 |
c5d.18xlarge | 72 | 144.00 |
c5d.24xlarge | 96 | 192.00 |
c5d.metal | 96 | 192.00 |
c5n.large | 2 | 5.25 |
c5n.xlarge | 4 | 10.50 |
c5n.2xlarge | 8 | 21.00 |
c5n.4xlarge | 16 | 42.00 |
c5n.9xlarge | 36 | 96.00 |
c5n.18xlarge | 72 | 192.00 |
c5n.metal | 72 | 192.00 |
c6a.large | 2 | 4.00 |
c6a.xlarge | 4 | 8.00 |
c6a.2xlarge | 8 | 16.00 |
c6a.4xlarge | 16 | 32.00 |
c6a.8xlarge | 32 | 64.00 |
c6a.12xlarge | 48 | 96.00 |
c6a.16xlarge | 64 | 128.00 |
c6a.24xlarge | 96 | 192.00 |
c6a.32xlarge | 128 | 256.00 |
c6a.48xlarge | 192 | 384.00 |
c6a.metal | 192 | 384.00 |
c6i.large | 2 | 4.00 |
c6i.xlarge | 4 | 8.00 |
c6i.2xlarge | 8 | 16.00 |
c6i.4xlarge | 16 | 32.00 |
c6i.8xlarge | 32 | 64.00 |
c6i.12xlarge | 48 | 96.00 |
c6i.16xlarge | 64 | 128.00 |
c6i.24xlarge | 96 | 192.00 |
c6i.32xlarge | 128 | 256.00 |
c6i.metal | 128 | 256.00 |
c6id.large | 2 | 4.00 |
c6id.xlarge | 4 | 8.00 |
c6id.2xlarge | 8 | 16.00 |
c6id.4xlarge | 16 | 32.00 |
c6id.8xlarge | 32 | 64.00 |
c6id.12xlarge | 48 | 96.00 |
c6id.16xlarge | 64 | 128.00 |
c6id.24xlarge | 96 | 192.00 |
c6id.32xlarge | 128 | 256.00 |
c6id.metal | 128 | 256.00 |
c6in.large | 2 | 4.00 |
c6in.xlarge | 4 | 8.00 |
c6in.2xlarge | 8 | 16.00 |
c6in.4xlarge | 16 | 32.00 |
c6in.8xlarge | 32 | 64.00 |
c6in.12xlarge | 48 | 96.00 |
c6in.16xlarge | 64 | 128.00 |
c6in.24xlarge | 96 | 192.00 |
c6in.32xlarge | 128 | 256.00 |
c6in.metal | 128 | 256.00 |
c7a.medium | 1 | 2.00 |
c7a.large | 2 | 4.00 |
c7a.xlarge | 4 | 8.00 |
c7a.2xlarge | 8 | 16.00 |
c7a.4xlarge | 16 | 32.00 |
c7a.8xlarge | 32 | 64.00 |
c7a.12xlarge | 48 | 96.00 |
c7a.16xlarge | 64 | 128.00 |
c7a.24xlarge | 96 | 192.00 |
c7a.32xlarge | 128 | 256.00 |
c7a.48xlarge | 192 | 384.00 |
c7a.metal-48xl | 192 | 384.00 |
c7i.large | 2 | 4.00 |
c7i.xlarge | 4 | 8.00 |
c7i.2xlarge | 8 | 16.00 |
c7i.4xlarge | 16 | 32.00 |
c7i.8xlarge | 32 | 64.00 |
c7i.12xlarge | 48 | 96.00 |
c7i.16xlarge | 64 | 128.00 |
c7i.24xlarge | 96 | 192.00 |
c7i.48xlarge | 192 | 384.00 |
c7i.metal-24xl | 96 | 192.00 |
c7i.metal-48xl | 192 | 384.00 |
hpc7a.12xlarge | 24 | 768.00 |
hpc7a.24xlarge | 48 | 768.00 |
hpc7a.48xlarge | 96 | 768.00 |
hpc7a.96xlarge | 192 | 768.00 |
The compute optimized instances use the following processors.
AMD processors
-
2nd generation AMD EPYC processors (AMD EPYC 7R32): C5a, C5ad
-
3rd generation AMD EPYC processors (AMD EPYC 7R13): C6a, Hpc6a
-
4th generation AMD EPYC processors (AMD EPYC 9R14): C7a, Hpc7a
Intel processors
-
Intel Xeon Scalable processors (Haswell E5-2666 v3): C4
-
Intel Xeon Scalable processors (Skylake 8124): C5n
-
Intel Xeon Scalable processors (Skylake 8124M or Cascade Lake 8223CL): Smaller C5 and C5d
-
2nd generation Intel Xeon Scalable processors (Cascade Lake 8275CL): Larger C5 and C5d
-
3rd generation Intel Xeon Scalable processors (Ice Lake 8375C): C6i, C6id
-
4th generation Intel Xeon Scalable processors (Sapphire Rapids 8488C): C7i
For more information, see Amazon EC2 Instance Types
Instance performance
EBS-optimized instances enable you to get consistently high performance for your EBS volumes by eliminating contention between Amazon EBS I/O and other network traffic from your instance. Some compute optimized instances are EBS-optimized by default at no additional cost. For more information, see Amazon EBS–optimized instances.
Network performance
You can enable enhanced networking on supported instance types to provide lower latencies, lower network jitter, and higher packet-per-second (PPS) performance. Most applications do not consistently need a high level of network performance, but can benefit from access to increased bandwidth when they send or receive data. For more information, see Enhanced networking on Windows.
The following is a summary of network performance for compute optimized instances that support enhanced networking.
Note
Instance types indicated with a † have a baseline bandwidth and can use a network I/O credit mechanism to burst beyond their baseline bandwidth on a best effort basis. For more information, see instance network bandwidth.
Instance type | Network performance | Enhanced networking features |
---|---|---|
c1.medium |
Moderate | Not supported |
c1.xlarge |
High | Not supported |
c3.large |
Moderate | Not supported |
c3.xlarge |
Moderate | Not supported |
c3.2xlarge |
High | Not supported |
c3.4xlarge |
High | Not supported |
c3.8xlarge |
10 Gigabit | Not supported |
c4.large |
Moderate | Not supported |
c4.xlarge |
High | Not supported |
c4.2xlarge |
High | Not supported |
c4.4xlarge |
High | Not supported |
c4.8xlarge |
10 Gigabit | Not supported |
c5.large † |
Up to 10 Gigabit | ENA |
c5.xlarge † |
Up to 10 Gigabit | ENA |
c5.2xlarge † |
Up to 10 Gigabit | ENA |
c5.4xlarge † |
Up to 10 Gigabit | ENA |
c5.9xlarge |
12 Gigabit | ENA |
c5.12xlarge |
12 Gigabit | ENA |
c5.18xlarge |
25 Gigabit | ENA |
c5.24xlarge |
25 Gigabit | ENA |
c5.metal |
25 Gigabit | ENA |
c5a.large † |
Up to 10 Gigabit | ENA |
c5a.xlarge † |
Up to 10 Gigabit | ENA |
c5a.2xlarge † |
Up to 10 Gigabit | ENA |
c5a.4xlarge † |
Up to 10 Gigabit | ENA |
c5a.8xlarge |
10 Gigabit | ENA |
c5a.12xlarge |
12 Gigabit | ENA |
c5a.16xlarge |
20 Gigabit | ENA |
c5a.24xlarge |
20 Gigabit | ENA |
c5ad.large † |
Up to 10 Gigabit | ENA |
c5ad.xlarge † |
Up to 10 Gigabit | ENA |
c5ad.2xlarge † |
Up to 10 Gigabit | ENA |
c5ad.4xlarge † |
Up to 10 Gigabit | ENA |
c5ad.8xlarge |
10 Gigabit | ENA |
c5ad.12xlarge |
12 Gigabit | ENA |
c5ad.16xlarge |
20 Gigabit | ENA |
c5ad.24xlarge |
20 Gigabit | ENA |
c5d.large † |
Up to 10 Gigabit | ENA |
c5d.xlarge † |
Up to 10 Gigabit | ENA |
c5d.2xlarge † |
Up to 10 Gigabit | ENA |
c5d.4xlarge † |
Up to 10 Gigabit | ENA |
c5d.9xlarge |
12 Gigabit | ENA |
c5d.12xlarge |
12 Gigabit | ENA |
c5d.18xlarge |
25 Gigabit | ENA |
c5d.24xlarge |
25 Gigabit | ENA |
c5d.metal |
25 Gigabit | ENA |
c5n.large † |
Up to 25 Gigabit | ENA |
c5n.xlarge † |
Up to 25 Gigabit | ENA |
c5n.2xlarge † |
Up to 25 Gigabit | ENA |
c5n.4xlarge † |
Up to 25 Gigabit | ENA |
c5n.9xlarge |
50 Gigabit | ENA | EFA |
c5n.18xlarge |
100 Gigabit | ENA | EFA |
c5n.metal |
100 Gigabit | ENA | EFA |
c6a.large † |
Up to 12.5 Gigabit | ENA |
c6a.xlarge † |
Up to 12.5 Gigabit | ENA |
c6a.2xlarge † |
Up to 12.5 Gigabit | ENA |
c6a.4xlarge † |
Up to 12.5 Gigabit | ENA |
c6a.8xlarge |
12.5 Gigabit | ENA |
c6a.12xlarge |
18.75 Gigabit | ENA |
c6a.16xlarge |
25 Gigabit | ENA |
c6a.24xlarge |
37.5 Gigabit | ENA |
c6a.32xlarge |
50 Gigabit | ENA |
c6a.48xlarge |
50 Gigabit | ENA | EFA |
c6a.metal |
50 Gigabit | ENA | EFA |
c6i.large † |
Up to 12.5 Gigabit | ENA |
c6i.xlarge † |
Up to 12.5 Gigabit | ENA |
c6i.2xlarge † |
Up to 12.5 Gigabit | ENA |
c6i.4xlarge † |
Up to 12.5 Gigabit | ENA |
c6i.8xlarge |
12.5 Gigabit | ENA |
c6i.12xlarge |
18.75 Gigabit | ENA |
c6i.16xlarge |
25 Gigabit | ENA |
c6i.24xlarge |
37.5 Gigabit | ENA |
c6i.32xlarge |
50 Gigabit | ENA | EFA |
c6i.metal |
50 Gigabit | ENA | EFA |
c6id.large † |
Up to 12.5 Gigabit | ENA |
c6id.xlarge † |
Up to 12.5 Gigabit | ENA |
c6id.2xlarge † |
Up to 12.5 Gigabit | ENA |
c6id.4xlarge † |
Up to 12.5 Gigabit | ENA |
c6id.8xlarge |
12.5 Gigabit | ENA |
c6id.12xlarge |
18.75 Gigabit | ENA |
c6id.16xlarge |
25 Gigabit | ENA |
c6id.24xlarge |
37.5 Gigabit | ENA |
c6id.32xlarge |
50 Gigabit | ENA | EFA |
c6id.metal |
50 Gigabit | ENA | EFA |
c6in.large † |
Up to 25 Gigabit | ENA |
c6in.xlarge † |
Up to 30 Gigabit | ENA |
c6in.2xlarge † |
Up to 40 Gigabit | ENA |
c6in.4xlarge † |
Up to 50 Gigabit | ENA |
c6in.8xlarge |
50 Gigabit | ENA |
c6in.12xlarge |
75 Gigabit | ENA |
c6in.16xlarge |
100 Gigabit | ENA |
c6in.24xlarge |
150 Gigabit | ENA |
c6in.32xlarge |
200 Gigabit | ENA | EFA |
c6in.metal |
200 Gigabit | ENA | EFA |
c7a.medium † |
Up to 12.5 Gigabit | ENA |
c7a.large † |
Up to 12.5 Gigabit | ENA |
c7a.xlarge † |
Up to 12.5 Gigabit | ENA |
c7a.2xlarge † |
Up to 12.5 Gigabit | ENA |
c7a.4xlarge † |
Up to 12.5 Gigabit | ENA |
c7a.8xlarge |
12.5 Gigabit | ENA |
c7a.12xlarge |
18.75 Gigabit | ENA |
c7a.16xlarge |
25 Gigabit | ENA |
c7a.24xlarge |
37.5 Gigabit | ENA |
c7a.32xlarge |
50 Gigabit | ENA |
c7a.48xlarge |
50 Gigabit | ENA | EFA |
c7a.metal-48xl |
50 Gigabit | ENA | EFA |
c7i.large † |
Up to 12.5 Gigabit | ENA |
c7i.xlarge † |
Up to 12.5 Gigabit | ENA |
c7i.2xlarge † |
Up to 12.5 Gigabit | ENA |
c7i.4xlarge † |
Up to 12.5 Gigabit | ENA |
c7i.8xlarge |
12.5 Gigabit | ENA |
c7i.12xlarge |
18.75 Gigabit | ENA |
c7i.16xlarge |
25 Gigabit | ENA |
c7i.24xlarge |
37.5 Gigabit | ENA |
c7i.48xlarge |
50 Gigabit | ENA | EFA |
c7i.metal-24xl |
37.5 Gigabit | ENA |
c7i.metal-48xl |
50 Gigabit | ENA | EFA |
hpc7a.12xlarge |
300 Gigabit | ENA | EFA |
hpc7a.24xlarge |
300 Gigabit | ENA | EFA |
hpc7a.48xlarge |
300 Gigabit | ENA | EFA |
hpc7a.96xlarge |
300 Gigabit | ENA | EFA |
For 32xlarge
and metal
instance types that support 200 Gbps, at
least 2 ENIs, each attached to a different network card, are required on the instance to
achieve 200 Gbps throughput. Each ENI attached to a network card can achieve a max of 170
Gbps.
The following table shows the baseline and burst bandwidth for instance types that use the network I/O credit mechanism to burst beyond their baseline bandwidth.
Instance type | Baseline bandwidth (Gbps) | Burst bandwidth (Gbps) |
---|---|---|
c5.large |
0.75 | 10.0 |
c5.xlarge |
1.25 | 10.0 |
c5.2xlarge |
2.5 | 10.0 |
c5.4xlarge |
5.0 | 10.0 |
c5a.large |
0.75 | 10.0 |
c5a.xlarge |
1.25 | 10.0 |
c5a.2xlarge |
2.5 | 10.0 |
c5a.4xlarge |
5.0 | 10.0 |
c5ad.large |
0.75 | 10.0 |
c5ad.xlarge |
1.25 | 10.0 |
c5ad.2xlarge |
2.5 | 10.0 |
c5ad.4xlarge |
5.0 | 10.0 |
c5d.large |
0.75 | 10.0 |
c5d.xlarge |
1.25 | 10.0 |
c5d.2xlarge |
2.5 | 10.0 |
c5d.4xlarge |
5.0 | 10.0 |
c5n.large |
3.0 | 25.0 |
c5n.xlarge |
5.0 | 25.0 |
c5n.2xlarge |
10.0 | 25.0 |
c5n.4xlarge |
15.0 | 25.0 |
c6a.large |
0.781 | 12.5 |
c6a.xlarge |
1.562 | 12.5 |
c6a.2xlarge |
3.125 | 12.5 |
c6a.4xlarge |
6.25 | 12.5 |
c6i.large |
0.781 | 12.5 |
c6i.xlarge |
1.562 | 12.5 |
c6i.2xlarge |
3.125 | 12.5 |
c6i.4xlarge |
6.25 | 12.5 |
c6id.large |
0.781 | 12.5 |
c6id.xlarge |
1.562 | 12.5 |
c6id.2xlarge |
3.125 | 12.5 |
c6id.4xlarge |
6.25 | 12.5 |
c6in.large |
3.125 | 25.0 |
c6in.xlarge |
6.25 | 30.0 |
c6in.2xlarge |
12.5 | 40.0 |
c6in.4xlarge |
25.0 | 50.0 |
c7a.medium |
0.39 | 12.5 |
c7a.large |
0.781 | 12.5 |
c7a.xlarge |
1.562 | 12.5 |
c7a.2xlarge |
3.125 | 12.5 |
c7a.4xlarge |
6.25 | 12.5 |
c7i.large |
0.781 | 12.5 |
c7i.xlarge |
1.562 | 12.5 |
c7i.2xlarge |
3.125 | 12.5 |
c7i.4xlarge |
6.25 | 12.5 |
Amazon EBS I/O performance
Amazon EBS optimized instances use an optimized configuration stack and provide additional, dedicated capacity for Amazon EBS I/O. This optimization provides the best performance for your Amazon EBS volumes by minimizing contention between Amazon EBS I/O and other traffic from your instance.
For more information, see Amazon EBS–optimized instances.
SSD-based instance store volume I/O performance
If you use all the SSD-based instance store volumes available to your instance, you can get up to the IOPS (4,096 byte block size) performance listed in the following table (at queue depth saturation). Otherwise, you get lower IOPS performance.
Instance Size | 100% Random Read IOPS | Write IOPS |
---|---|---|
c5ad.large |
16,283 | 7,105 |
c5ad.xlarge |
32,566 | 14,211 |
c5ad.2xlarge |
65,132 | 28,421 |
c5ad.4xlarge |
130,263 | 56,842 |
c5ad.8xlarge |
260,526 | 113,684 |
c5ad.12xlarge |
412,500 | 180,000 |
c5ad.16xlarge |
521,053 | 227,368 |
c5ad.24xlarge |
825,000 | 360,000 |
c5d.large |
20,000 | 9,000 |
c5d.xlarge |
40,000 | 18,000 |
c5d.2xlarge |
80,000 | 37,000 |
c5d.4xlarge |
175,000 | 75,000 |
c5d.9xlarge |
350,000 | 170,000 |
c5d.12xlarge |
700,000 | 340,000 |
c5d.18xlarge |
700,000 | 340,000 |
c5d.24xlarge |
1,400,000 | 680,000 |
c5d.metal |
1,400,000 | 680,000 |
c6id.large |
33,542 | 16,771 |
c6id.xlarge |
67,083 | 33,542 |
c6id.2xlarge |
134,167 | 67,084 |
c6id.4xlarge |
268,333 | 134,167 |
c6id.8xlarge |
536,666 | 268,334 |
c6id.12xlarge |
804,999 | 402,501 |
c6id.16xlarge |
1,073,332 | 536,668 |
c6id.24xlarge |
1,609,998 | 805,002 |
c6id.32xlarge |
2,146,664 | 1,073,336 |
c6id.metal |
2,146,664 | 1,073,336 |
As you fill the SSD-based instance store volumes for your instance, the number of write IOPS that you can achieve decreases. This is due to the extra work the SSD controller must do to find available space, rewrite existing data, and erase unused space so that it can be rewritten. This process of garbage collection results in internal write amplification to the SSD, expressed as the ratio of SSD write operations to user write operations. This decrease in performance is even larger if the write operations are not in multiples of 4,096 bytes or not aligned to a 4,096-byte boundary. If you write a smaller amount of bytes or bytes that are not aligned, the SSD controller must read the surrounding data and store the result in a new location. This pattern results in significantly increased write amplification, increased latency, and dramatically reduced I/O performance.
SSD controllers can use several strategies to reduce the impact of write amplification. One such strategy is to reserve space in the SSD instance storage so that the controller can more efficiently manage the space available for write operations. This is called over-provisioning. The SSD-based instance store volumes provided to an instance don't have any space reserved for over-provisioning. To reduce write amplification, we recommend that you leave 10% of the volume unpartitioned so that the SSD controller can use it for over-provisioning. This decreases the storage that you can use, but increases performance even if the disk is close to full capacity.
For instance store volumes that support TRIM, you can use the TRIM command to notify the SSD controller whenever you no longer need data that you've written. This provides the controller with more free space, which can reduce write amplification and increase performance. For more information, see Instance store volume TRIM support.
Release notes
-
c7a.metal-48xl
instances do not support Windows Server 2019 AMIs released before July 2023, and Windows Server 2016 AMIs. -
C4 instances and instances built on the Nitro System require 64-bit EBS-backed HVM AMIs. They have high-memory and require a 64-bit operating system to take advantage of that capacity. HVM AMIs provide superior performance in comparison to paravirtual (PV) AMIs on high-memory instance types. In addition, you must use an HVM AMI to take advantage of enhanced networking.
-
Instances built on the Nitro System have the following requirements:
NVMe drivers must be installed
Elastic Network Adapter (ENA) drivers must be installed
The current Amazon Windows AMIs meet these requirements.
-
To get the best performance from your C6i instances, ensure that they have ENA driver version 2.2.3 or later. Using an ENA driver earlier than version 2.0.0 with these instances causes network interface attachment failures. The following AMIs have a compatible ENA driver.
Amazon Windows AMI from May 2021 or later
-
The maximum number of Amazon EBS volumes that you can attach to an instance depends on the instance type and instance size. For more information, see Instance volume limits.
-
Launching a bare metal instance boots the underlying server, which includes verifying all hardware and firmware components. This means that it can take 20 minutes from the time the instance enters the running state until it becomes available over the network.
-
To attach or detach EBS volumes or secondary network interfaces from a bare metal instance requires PCIe native hotplug support.
-
Bare metal instances use a PCI-based serial device rather than an I/O port-based serial device. The upstream Linux kernel and the latest Amazon Linux AMIs support this device. Bare metal instances also provide an ACPI SPCR table to enable the system to automatically use the PCI-based serial device. The latest Windows AMIs automatically use the PCI-based serial device.
-
There is a limit on the total number of instances that you can launch in a Region, and there are additional limits on some instance types. For more information, see How many instances can I run in Amazon EC2?
in the Amazon EC2 FAQ.