Stellar Cloud Resource policy
For Central Processing Unit configuration in our cloud platform we use Dual AMD Epyc 7401, Dual AMD Epyc 7352 or Single AMD Epyc 7401P for each host node
The difference between v(irtual)CPU and d(edicated)CPU is in the core usage guarantee.
vCPU means maximum 100% of 1x AMD Epyc 7401 Core and minimum 25% expressed by formula:
vCPU := 100% >= (1 x hostCPU) >= 25%
dCPU means 100% of dedicated 1x AMD Epyc 7401 Core expressed by formula:
dCPU := 1 x hostCPU
hostCPU is 1 Physical Core of 1 (one) AMD Epyc 7401 processor
We use DDR4 ECC Registered RAM with at least 2666Mhz rate for all types of RAM allocation
vMEM Memory is provided by virtual allocation with direct provision of used blocks of host physical RAM:
1MiB vMEM | 1MiB dMEM := Dedup(1MiB hostRAM - zeroBytes)
dMEM Memory is provided by preallocation of host physical RAM:
1MiB dMEM := 1MiB hostRAM
hostRAM means physical system ram presented by hypervisor host system
zeroBytes means bytes not containing any data (allocated but empty memory pages)
Dedup means data which is found in other hostRAM pages will not be duplicated but referenced
vMEM is virtually allocated on the host system and presented to the instance by reference through hypervisor.
dMEM is preallocated on the host system.
vNVME, vSSD or vHDD space imposes different limits in size, iops and bandwidth on the vBLOCK device.
In the plan listing we only specify the interface without specifying that it is a block device, because interface implies using a block device.
This means vBLOCK applies to any Stellar Cloud virtual plan and pBLOCK applies to any Stellar Cloud dedicated plan:
vBLOCK Device space is provided by virtual allocation with direct provision of used blocks of host LVM volumes:
1MiB vBlock := Dedup(1MiB hostBlock - zeroBytes)
pBLOCK Device space is provided by direct allocation of host LVM volumes:
1MiB pBlock := 1MiB hostBlock
vBLOCK devices = any interfaces prepended with v
pBLOCK devices = any interfaces prepended with p
Limits and QoS are imposed on all types of IO operations: Sequential Write, Sequential Read, Random Write, Random Read, Mixed.
Interfaces limits in detail:
vNVME := 1200000 >= IOPS >= 700
vNVME := 15000MB/s >= IOBW >= 75MB/s
vSSD := 120000 >= IOPS >= 100
vSSD := 2500MB/s >= IOBW >= 7MB/s
vHDD := 12000 >= IOPS >= 10
vHDD := 750MB/s >= IOBW >= 0.7MB/s
pNVME := 1200000 >= IOPS >= 1500
pNVME := 15000MB/s >= IOBW >= 155MB/s
pSSD := 120000 >= IOPS >= 250
pSSD := 2500MB/s >= IOBW >= 25MB/s
pHDD := 12000 >= IOPS >= 25
pHDD := 750MB/s >= IOBW >= 7MB/s
NVMe Devices used but not limited to Intel P4510, Micron 9300MAX.
SSD Devices used but not limited to Micron 1100.
HDD Devices used but not limited to Hitachi Ultrastar.
IOPS = input output operations per second
IOBW = input output bandwidth in MB/s
We use Dual 10Gbit/s bonding uplink to each host node. This section describes only the virtualized devices and their share of uplink resources.
vNET := IF (NTB > 0) THEN (1Gbit/s duplex >= vBW >= 10Mbit/s duplex) ELSE (vBW = 10Mbit/s duplex)
pNET := 10Gbit/s duplex >= vBW >= NBW * 1Mbit/s duplex
vNET, pNET = virtual machine interface represented by tap device in virtualization host system
vBW = available bandwidth
NTB = amount of available traffic in TB
NBW = chosen network speed plan
Please note that:
Due to nature of internet transit and peering the bandwidth which leaves and reaches our network externally depends on transit and peering of other networks as well and provided with our highest quality effort. Before filing a Resource Policy Investigation Case (RPIC) please ensure that the problem occurs within our network (ServerAstra AS56322) network. Tools like traceroute, mtr and ping will help you identify the issue and present us with a compelling case to escalate to network engineers.