The Alibaba Cloud Linux 4 container-optimized image is a highly optimized version of the standard Alibaba Cloud Linux 4 image that is designed for container workloads. It runs the ANCK 6.6 kernel and enables cgroup v2 by default to support finer-grained resource management. Developed by Alibaba Cloud based on extensive experience with ACK, this image is recommended for all containerized application deployments.
Features
In addition to the features of the standard Alibaba Cloud Linux 4 image, the container-optimized image provides the following features:
cgroup v2 enabled by default: Provides a unified API and more precise resource management, aligns with the direction of the Kubernetes community, and fully supports enhanced features such as MemoryQoS and PSI.
To ensure a smooth migration, Alibaba Cloud Linux 4 integrates systemd 255. This version introduces new capabilities while it maintains compatibility with cgroup v1 and supports manual switchover. However, Alibaba Cloud Linux 4 may be the last mainstream distribution to support cgroup v1. We recommend that you adapt your applications to ensure compatibility.
cgroup v2 and cgroup v1 have different interfaces. If your application directly accesses the cgroup file system, you must confirm its compatibility to prevent startup failures or abnormal reads of resource data. For more information, see Cgroup version guide.
Upgraded kernel and toolchain: Uses the upstream-based ANCK 6.6 kernel with multiple new features and integrates the updated glibc 2.38 and GCC 12.3.0 to deliver higher performance and a more modern runtime environment.
Thanks to these enhancements, Alibaba Cloud Linux 4 delivers significant performance gains. For example, it provides approximately 20% higher performance than Alibaba Cloud Linux 3 in multi-core scenarios and an average improvement of 3% in multi-database workloads.
The performance data is from a UnixBench 5.1.3 benchmark that was run concurrently on Alibaba Cloud Linux 3 and Alibaba Cloud Linux 4 on the same node with 192 CPUs and 384 GiB of memory. Actual results may vary based on your environment.
In addition, the Alibaba Cloud Linux 4 container-optimized image offers the following unique advantages:
Faster startup: Pre-integrates container runtimes and toolchains, which reduces the Kubernetes node initialization time by approximately 50% and improves scale-out efficiency.
Secure and trusted: All pre-installed software and toolchains undergo rigorous testing and performance tuning by Alibaba Cloud to ensure high stability, security, and reliability.
Out-of-the-box optimization: Applies system-level kernel parameter tuning for key metrics, such as network throughput, storage I/O, and memory management, to deliver best-practice configurations that are validated at a large scale in production environments.
Usage
Use in ACK (recommended): When you create a cluster or create a node pool, set the node operating system to Alibaba Cloud Linux 4 container-optimized.
To use a self-managed Kubernetes cluster on ECS, select the public image Alibaba Cloud Linux 4 container-optimized when creating an ECS instance.
Billing
The Alibaba Cloud Linux 4 container-optimized image is free of charge. However, you are charged for the resources that you use when you create nodes, such as ECS instances, VPC, and NAT Gateway. For more information, see Billing overview.