Overview

Large-memory ECSs provide an even larger amount of memory than memory-optimized ECSs. They are used for applications that require a large amount of memory, rapid data switching, low latency, and capability of processing large volumes of data. Large-memory ECSs provide large memory and high computing, storage, and network performance.

Applications
Large-memory ECSs are suitable for applications that require a large amount of memory, rapid data switching, and low latency, and process large volumes of data.
Application scenarios
OLTP and OLAP scenarios

Specifications

**Table 1** E6 ECS specifications
Flavor	vCPUs	Memory (GiB)	Max./Assured Bandwidth (Gbit/s)	Max. PPS (10,000)	Max. NIC Queues	Max. NICs	Virtualization	Hardware
e6.26xlarge.28	104	2948	30/20	550	16	8	KVM	CPU: Intel® Xeon® Skylake 8280
e6.52xlarge.28	208	5896	40/40	1,000	32	8	KVM	CPU: Intel® Xeon® Skylake 8280

**Table 2** E3 ECS specifications
Flavor	vCPUs	Memory (GiB)	Max./Assured Bandwidth (Gbit/s)	Max. PPS (10,000)	Max. NIC Queues	Max. NICs	Virtualization	Hardware
e3.7xlarge.12	28	348	25/12	280	8	8	KVM	CPU: Intel® Xeon® Skylake 6151
e3.14xlarge.12	56	696	25/25	500	16	8	KVM	CPU: Intel® Xeon® Skylake 6151
e3.26xlarge.14	104	1466	30/20	550	16	8	KVM	CPU: Intel® Xeon® Skylake 8176
e3.52xlarge.14	208	2932	40/40	1,000	32	8	KVM	CPU: Intel® Xeon® Skylake 8176

Notes

Large-memory ECSs do not support NIC hot swapping.
Specifications of large-memory ECSs can be modified only within the same flavor family.
Affected by the memory loading speed, large-memory ECSs may take longer to start.

Table 3 lists the OSs supported by large-memory ECSs.

**Table 3** Supported OS versions
OS	Version
CentOS	CentOS 7.9 64bit CentOS 7.7 64bit
EulerOS	EulerOS 2.5 64bit
Fedora	Fedora 35 64bit Fedora 34 64bit Fedora 33 64bit
OpenSUSE	OpenSUSE 15.3 64bit
Oracle Linux	Oracle Linux Server release 8.4 64bit Oracle Linux Server release 7.6 64bit
Red Hat	Red Hat Enterprise Linux 7.9 64bit
SUSE	Novell SUSE Linux Enterprise Server 15 SP3 64bit Novell SUSE Linux Enterprise Server 15 SP2 64bit Novell SUSE Linux Enterprise Server 15 SP1 64bit Novell SUSE Linux Enterprise Server 15 64bit Novell SUSE Linux Enterprise Server 12 SP5 64bit Novell SUSE Linux Enterprise Server 12 SP4 64bit Novell SUSE Linux Enterprise Server 12 SP3 64bit
Ubuntu	Ubuntu 20.04 server 64bit Ubuntu 18.04 server 64bit
Windows	Windows Server 2019 Standard 64bit Windows Server 2016 Standard 64bit Windows Server 2012 R2 Standard 64bit

Large-memory ECSs can use ultra-high I/O EVS disks as the system disk and data disks.

The primary and extension NICs of a large-memory ECS can only be used in the scenarios listed in Table 4.

**Table 4** Application scenarios of the NICs of a large-memory ECS
NIC Type	Application Scenario	Remarks
Primary NIC	Vertical layer 3 communication	N/A
Extension NIC	Horizontal layer 2 communication	To improve network performance, you can set the MTU of an extension NIC to 8888.

An ECS can have a maximum of 60 attached disks, including the system disk. For details about constraints, see Can I Attach Multiple Disks to an ECS?
For example, an E3 ECS can have one system disk and 59 EVS disks.

Large-Memory ECSs

Overview

Specifications

Notes