Instance Specification
This page describes the instance families, sizing options, and underlying hardware available for Zenlayer Elastic Compute (ZEC) instances. Use it to choose the right instance shape for your workload and understand the CPU and GPU hardware behind each family.
1. Instance Families
ZEC offers six instance families, split by CPU vendor and by whether they back standard compute or GPU-attached instances:
z2a
Standard CPU
AMD EPYC 2nd Gen (Rome)
EPYC 7H12
z4a
Standard CPU
AMD EPYC 4th Gen (Genoa)
EPYC 9654
z4ah
Standard CPU
AMD EPYC 4th Gen (Genoa)
EPYC 9554
z2i
Standard CPU
Intel Xeon Scalable 2nd Gen (Cascade Lake)
Xeon Gold 6254 · Xeon Gold 6248
z3a
GPU instance
AMD EPYC 3rd Gen (Milan)
EPYC 7543
z4i
GPU instance
Intel Xeon Scalable 4th Gen (Sapphire Rapids)
Xeon Gold 6430
GPU instance families (z3a, z4i) are deployed exclusively in GPU-enabled instances and are not available as standard compute.
z4ah is currently available only in the ZEC Mumbai region.
2. vCPU-to-RAM Ratios
Each family supports three ratio types so you can match your workload's memory profile:
CPU Intensive
1:2
Compute-bound workloads — batch processing, encoding, simulation
Standard
1:4
General-purpose workloads — web servers, application servers, APIs
Memory Intensive
1:8
Memory-bound workloads — caches, in-memory databases, analytics
Instance sizes scale from 1 vCPU up to 64 vCPU within each ratio type. For example, a z2a.std.16 is a 2nd-gen AMD instance with the 1:4 standard ratio and 16 vCPUs (16 vCPU / 64 GiB RAM).
3. vNIC and Networking Limits
Networking limits scale with instance size. The vNIC columns (Max vNICs, vNIC Multi-Queue, Private IPv4 per vNIC) are identical across all instance families; egress bandwidth and PPS depend on the family. A — in the Egress PPS column means the family has no PPS limit.
z4a, z4ah
1
2
1
6
1 Gbps
500 Kpps
2
2
1
10
2 Gbps
900 Kpps
4
2
2
15
4 Gbps
1 Mpps
8
2
4
15
6 Gbps
1.6 Mpps
16
4
8
30
10 Gbps
2 Mpps
32
8
16
30
16 Gbps
3 Mpps
64
16
32
30
22 Gbps
6 Mpps
All other families (z2a, z2i, z3a, z4i)
1
2
1
6
1 Gbps
—
2
2
1
10
2 Gbps
—
4
2
2
15
4 Gbps
—
8
2
4
15
6 Gbps
—
16
4
8
30
10 Gbps
—
32
8
16
30
16 Gbps
—
64
16
32
30
20 Gbps
—
Max vNICs: Maximum number of virtual network interfaces (including the primary vNIC) you can attach to an instance.
vNIC Multi-Queue: Number of transmit (Tx) and receive (Rx) queues per vNIC. Higher counts improve network throughput and reduce latency.
Private IPv4 per vNIC: Maximum private IPv4 addresses that can be assigned to a single vNIC.
Egress Bandwidth: Maximum egress (outbound) bandwidth for the instance.
Egress PPS: Maximum egress packet-per-second throughput. — means no PPS limit.
4. Regional Availability
Available instance sizes vary by location depending on inventory. Check the Zenlayer console when creating an instance to see what's available in your target region.
5. CPU Specifications
5.1 z2a — AMD EPYC 2nd Gen (Rome)
AMD EPYC 7H12
Generation
AMD EPYC 2nd Gen (Rome)
Microarchitecture
Zen 2
Socket
SP3
Cores / Threads
64 / 128
Base Clock
2.60 GHz
Max Boost Clock
3.30 GHz
L2 Cache
32 MB (512 KB × 64)
L3 Cache
256 MB
Memory Controller
8-channel DDR4
Max Memory Speed
DDR4-3200
Max Memory Capacity
2 TB (4 TB with 3DS RDIMMs)
PCIe Version
PCIe 4.0
PCIe Lanes
128 per socket
TDP
280 W
Process Node
TSMC 7 nm (N7)
5.2 z3a — AMD EPYC 3rd Gen (Milan)
AMD EPYC 7543 (GPU instances only)
Generation
AMD EPYC 3rd Gen (Milan)
Microarchitecture
Zen 3
Socket
SP3
Cores / Threads
32 / 64
Base Clock
2.80 GHz
Max Boost Clock
3.70 GHz
L2 Cache
16 MB (512 KB × 32)
L3 Cache
128 MB
Memory Controller
8-channel DDR4
Max Memory Speed
DDR4-3200
Max Memory Capacity
2 TB (4 TB with 3DS RDIMMs)
PCIe Version
PCIe 4.0
PCIe Lanes
128 per socket
TDP
225 W
Process Node
TSMC 7 nm (N7P)
5.3 z4a — AMD EPYC 4th Gen (Genoa)
AMD EPYC 9654
Generation
AMD EPYC 4th Gen (Genoa)
Microarchitecture
Zen 4
Socket
SP5
Cores / Threads
96 / 192
Base Clock
2.40 GHz
Max Boost Clock
3.70 GHz
L2 Cache
96 MB (1 MB × 96)
L3 Cache
384 MB
Memory Controller
12-channel DDR5
Max Memory Speed
DDR5-4800
Max Memory Capacity
6 TB
PCIe Version
PCIe 5.0
PCIe Lanes
128 per socket
TDP
360 W
Process Node
TSMC 5 nm (N5)
5.4 z4ah — AMD EPYC 4th Gen (Genoa)
AMD EPYC 9554 (ZEC Mumbai only)
Generation
AMD EPYC 4th Gen (Genoa)
Microarchitecture
Zen 4
Socket
SP5
Cores / Threads
64 / 128
Base Clock
3.10 GHz
Max Boost Clock
3.75 GHz
L2 Cache
64 MB (1 MB × 64)
L3 Cache
256 MB
Memory Controller
12-channel DDR5
Max Memory Speed
DDR5-4800
Max Memory Capacity
6 TB
PCIe Version
PCIe 5.0
PCIe Lanes
128 per socket
TDP
360 W
Process Node
TSMC 5 nm (N5)
5.5 z2i — Intel Xeon Scalable 2nd Gen (Cascade Lake)
Intel Xeon Gold 6254
Generation
2nd Gen Intel Xeon Scalable (Cascade Lake)
Microarchitecture
Cascade Lake
Socket
LGA 3647 (P0)
Cores / Threads
18 / 36
Base Clock
3.10 GHz
Max Turbo Frequency
4.00 GHz
L2 Cache
18 MB
L3 Cache (LLC)
24.75 MB
Memory Controller
6-channel DDR4
Max Memory Speed
DDR4-2933
Max Memory Capacity
1 TB per socket
PCIe Version
PCIe 3.0
PCIe Lanes
48 per socket
TDP
200 W
Process Node
Intel 14 nm++
Intel Xeon Gold 6248
Generation
2nd Gen Intel Xeon Scalable (Cascade Lake)
Microarchitecture
Cascade Lake
Socket
LGA 3647 (P0)
Cores / Threads
20 / 40
Base Clock
2.50 GHz
Max Turbo Frequency
3.90 GHz
L2 Cache
20 MB
L3 Cache (LLC)
27.50 MB
Memory Controller
6-channel DDR4
Max Memory Speed
DDR4-2933
Max Memory Capacity
1 TB per socket
PCIe Version
PCIe 3.0
PCIe Lanes
48 per socket
TDP
150 W
Process Node
Intel 14 nm++
5.6 z4i — Intel Xeon Scalable 4th Gen (Sapphire Rapids)
Intel Xeon Gold 6430 (GPU instances only)
Generation
4th Gen Intel Xeon Scalable (Sapphire Rapids)
Microarchitecture
Sapphire Rapids
Socket
LGA 4677
Cores / Threads
32 / 64
Base Clock
2.10 GHz
Max Turbo Frequency
3.40 GHz
L2 Cache
40 MB
L3 Cache (LLC)
60 MB
Memory Controller
8-channel DDR5
Max Memory Speed
DDR5-4800
Max Memory Capacity
4 TB per socket
PCIe Version
PCIe 5.0
PCIe Lanes
80 per socket
TDP
270 W
Process Node
Intel 7 (10 nm ESF)
6. GPU Specifications
NVIDIA GeForce RTX 4090
Architecture
Ada Lovelace
GPU Die
AD102
CUDA Cores
16,384
Tensor Cores
512 (4th Gen)
RT Cores
128 (3rd Gen)
GPU Memory
24 GB GDDR6X
Memory Bus Width
384-bit
Memory Bandwidth
1,008 GB/s
Memory Speed
21 Gbps
L2 Cache
72 MB
FP32 Performance
82.6 TFLOPS
FP16 Performance
165.2 TFLOPS (non-sparse)
TF32 Tensor Performance
82.6 TFLOPS (non-sparse) / 330.3 TFLOPS (sparse)
Boost Clock
2,520 MHz
Interface
PCIe 4.0 x16
TDP
450 W
Process Node
TSMC 4 nm (N4)
Launch Date
October 2022
NVIDIA Tesla T4
Architecture
Turing
GPU Die
TU104
CUDA Cores
2,560
Tensor Cores
320 (2nd Gen)
GPU Memory
16 GB GDDR6
Memory Bandwidth
320 GB/s
FP32 Performance
8.1 TFLOPS
FP16 Performance
65 TFLOPS (with sparsity)
INT8 Performance
130 TOPS
INT4 Performance
260 TOPS
ECC
Supported
Interface
PCIe 3.0 x16
Form Factor
Low-profile, single-slot
TDP
70 W
Process Node
TSMC 12 nm
Launch Date
September 2018
Last updated