Network bandwidth

Google Cloud accounts for bandwidth per virtual machine (VM) instance, not per network interface (vNIC) or IP address. A VM's machine type defines its maximum possible egress rate; however, you can only achieve that maximum possible egress rate in specific situations.

This page outlines expectations, which are useful when planning your deployments. It categorizes bandwidth using two dimensions:

  • Egress or ingress: As used on this page, egress and ingress are always from the perspective of a Google Cloud VM:
    • Packets sent from a Google Cloud VM compose its egress (outbound) traffic.
    • Packets sent to a Google Cloud VM compose its ingress (inbound) traffic.
  • How the packet is routed: A packet can be routed from a sending VM or to a receiving VM using routes whose next hops are within a VPC network or routes outside of a VPC network.

Neither additional virtual network interfaces (vNICs) nor additional IP addresses per vNIC increase ingress or egress bandwidth for a VM. For example, an n1-standard-8 VM with two NICs is limited to 16 Gbps total egress bandwidth, not 16 Gbps egress bandwidth per vNIC.

All of the information on this page is applicable to Compute Engine VMs, as well as products that depend on Compute Engine VMs. For example, a Google Kubernetes Engine node is a Compute Engine VM.

Bandwidth summary

The following table illustrates bandwidth expectations based on whether a packet is sent from (egress) or received by (ingress) a VM and the packet routing method.

Egress

Bandwidth expectations
Routing within a VPC network

  • Primarily defined by a per-VM maximum egress bandwidth based on the sending VM's machine type and whether Tier_1 networking is enabled.

    • N2, N2D, C2, and C2D VMs with Tier_1 networking support egress bandwidth limits up to 100 Gbps.
    • H3 VMs support VM-to-VM egress bandwidth limits up to 200 Gbps.
    • C3 and C3D VMs support up to 200 Gbps egress bandwidth limits with Tier_1 networking.
  • For other factors, definitions, and scenarios, see Egress to destinations routable within a VPC network.
Routing outside a VPC network

  • Primarily defined by a per-VM maximum egress bandwidth based on the sending VM's machine type and whether Tier_1 networking is enabled. Except for H3 VMs, a sending VM's maximum possible egress to a destination outside of its VPC network cannot exceed the following:

    • 7 Gbps total when Tier_1 networking isn't enabled
    • 25 Gbps total when Tier_1 networking is enabled
    • 3 Gbps per flow
  • For other factors, definitions, and caveats, see Egress to destinations outside of a VPC network.

Ingress

Bandwidth expectations
Routing within a VPC network
  • Generally, ingress rates are similar to the egress rates for a machine type.
  • The size of your VM, the capacity of the server NIC, the traffic coming into other guest VMs running on the same host hardware, your guest OS network configuration, and the number of disk reads performed by your VM can all impact the ingress rate.
  • Google Cloud doesn't impose any additional limitations on ingress rates within a VPC network.
  • For other factors, definitions, and scenarios, see Ingress to destinations routable within a VPC network.
Routing outside a VPC network

  • Google Cloud protects each VM by limiting ingress traffic routed outside a VPC network. The limit is the first of the following rates encountered:

    • 1,800,000 pps (packets per second)
    • 30 Gbps
  • For other factors, definitions, and scenarios, see Ingress to to destinations outside of a VPC network.

Egress bandwidth

Google Cloud limits outbound (egress) bandwidth using per-VM maximum egress rates based the machine type of the VM sending the packet and whether the packet's destination is accessible using routes within a VPC network or routes outside of a VPC network. Outbound bandwidth includes packets emitted by all of the VM's NICs and data transferred to all persistent disks connected to the VM.

Per-VM maximum egress bandwidth

Per-VM maximum egress bandwidth is generally 2 Gbps per vCPU, but there are some differences and exceptions, depending on the machine series. The following table shows the range of maximum limits for egress bandwidth for traffic routed within a VPC network for standard networking tier only, not per VM Tier_1 networking performance.

Machine series Lowest per-VM maximum egress limit without Tier_1 networking Highest per-VM maximum egress limit without Tier_1 networking
E2 1 Gbps 16 Gbps
C3 23 Gbps 100 Gbps
C3D 20 Gbps 100 Gbps
T2D 10 Gbps 32 Gbps
N2,C2, N2D, and C2D 10 Gbps 32 Gbps
H3 N/A 200 Gbps
N1 (excluding VMs with 1 vCPU) 10 Gbps 32 Gbps on Intel Skylake CPU platform
16 Gbps on CPU platforms older than Intel Skylake
N1 machine types with 1 vCPU, f1-micro, and g1-small 2 Gbps 2 Gbps
A2 and G2 Based on GPUs Based on GPUs

You can find the per-VM maximum egress bandwidth for every machine type listed on its specific machine family page:

Per-VM maximum egress bandwidth is not a guarantee. Actual egress bandwidth can be lowered according to factors such as the following non-exhaustive list:

  • Guest Ethernet driver—gVNIC offers better performance than the VirtIO network interface
  • Packet size
  • Protocol overhead
  • The number of flows
  • Ethernet driver settings of the VM's guest OS, such as checksum offload and TCP segmentation offload (TSO)
  • Network congestion
  • In a situation where persistent disks compete with other network egress traffic, 60% of the maximum network bandwidth is given to Persistent Disk writes, leaving 40% for other network egress traffic. See Factors that affect disk performance in the Persistent Disk documentation for more details.

To get the largest possible per-VM maximum egress bandwidth:

Egress to destinations routable within a VPC network

From the perspective of a sending VM and for destination IP addresses accessible by means of routes within a VPC network, Google Cloud limits outbound traffic using these rules:

  • Per-VM maximum egress bandwidth: The per-VM maximum egress bandwidth described in the Per-VM maximum egress bandwidth section.
  • Per-project inter-regional egress bandwidth: If a sending VM and an internal destination or its next hop are in different regions, Google Cloud enforces a maximum inter-regional egress bandwidth limit. Most customers are unlikely to reach this limit. For questions about this limit, file a support case.
  • Cloud VPN and Cloud Interconnect limits: When sending traffic from a VM to an internal IP address destination routable by a next hop Cloud VPN tunnel or Cloud Interconnect VLAN attachment, egress bandwidth is limited by:

Destinations routable within a VPC network include all of the following destinations, each of which is accessible from the perspective of the sending VM by a route whose next hop is not the default internet gateway:

  • Regional internal IPv4 addresses in subnet primary IPv4 and subnet secondary IPv4 address ranges, including private IPv4 address ranges and privately used public IPv4 address ranges, used by these destination resources:
    • The primary internal IPv4 address of a receiving VM's network interface (vNIC). (When a sending VM connects to another VM's vNIC external IPv4 address, packets are routed using a next hop default internet gateway, so Egress to destinations outside of a VPC network applies instead.)
    • An internal IPv4 address in an alias IP range of a receiving VM's vNIC.
    • An internal IPv4 address of an internal forwarding rule for either protocol forwarding or for an internal passthrough Network Load Balancer.
  • Global internal IPv4 addresses for these destination resources:
  • Internal IPv6 subnet address ranges used by these destination resources:
    • An IPv6 address from the /96 IPv6 address range assigned to a dual-stack receiving VM's vNIC.
    • An IPv6 address from the /96 IPv6 address range of an internal forwarding rule for either protocol forwarding or for an internal passthrough Network Load Balancer.
  • External IPv6 subnet address ranges used by these destination resources when packets are routed using subnet routes or peering subnet routes within the VPC network or by custom routes within the VPC network that do not use the default internet gateway next hop:
    • An IPv6 address from the /96 IPv6 address range assigned to a dual-stack receiving VM's vNIC.
    • An IPv6 address from the /96 IPv6 address range of an external forwarding rule for either protocol forwarding or for an external passthrough Network Load Balancer.
  • Other destinations accessible using the following VPC network routes:

The following list ranks traffic from sending VMs to internal destinations, from highest possible bandwidth to lowest:

Egress to destinations outside of a VPC network

From the perspective of a sending VM and for destination IP addresses outside of a VPC network, Google Cloud limits outbound traffic to whichever of the following rates is reached first:

  • Per-VM egress bandwidth: The maximum bandwidth for all connections from a VM to destinations outside of a VPC network is the smaller of the Per-VM maximum egress bandwidth and one of these rates:

    • 25 Gbps, if Tier_1 networking is enabled
    • 7 Gbps, if Tier_1 networking is not enabled
    • 1 Gbps for H3 VMs

    As an example, even though an n2-standard-16 instance has a per-VM maximum egress bandwidth of 32 Gbps, the per-VM egress bandwidth from an n2-standard-16 instance to external destinations is either 25 Gbps or 7 Gbps, depending on whether Tier_1 networking is enabled.

  • Per-flow maximum egress rate: The maximum bandwidth for each unique 5-tuple connection, from a VM to a destination outside of a VPC network is 3 Gbps, except on H3, where it is 1 Gbps.

  • Per-project internet egress bandwidth: The maximum bandwidth for all connections from VMs in each region of a project to destinations outside of a VPC network is defined by the project's Internet egress bandwidth quotas.

Destinations outside of a VPC network include all of the following destinations, each of which is accessible by a route in the sending VM's VPC network whose next hop is the default internet gateway:

  • Global external IPv4 and IPv6 addresses for external proxy Network Load Balancers and external Application Load Balancers
  • Regional external IPv4 addresses for Google Cloud resources, including VM vNIC external IPv4 addresses, external IPv4 addresses for external protocol forwarding, external passthrough Network Load Balancers, and response packets to Cloud NAT gateways.
  • Regional external IPv6 addresses in dual-stack subnets with external IPv6 address ranges used by dual-stack VM external IPv6 addresses, external protocol forwarding, and external passthrough Network Load Balancers, provided that the subnet is located in a separate, non-peered VPC network and the destination IPv6 address range is accessible using a route in the sending VM's VPC network whose next hop is the default internet gateway. If a dual-stack subnet with an external IPv6 address range is located in the same VPC network or in a peered VPC network, see Egress to destinations routable within a VPC network instead.
  • Other external destinations accessible using a static route in the sending VM's VPC network provided that the next hop for the route is the default internet gateway.

For details about which Google Cloud resources use what types of external IP addresses, see External IP addresses.

Ingress bandwidth

Google Cloud handles inbound (ingress) bandwidth depending on how the incoming packet is routed to a receiving VM.

Ingress to destinations routable within a VPC network

A receiving VM can handle as many incoming packets as its machine type, operating system, and other network conditions permit. Google Cloud does not implement any purposeful bandwidth restriction on incoming packets delivered to a VM if the incoming packet is delivered using routes within a VPC network:

  • Subnet routes in the receiving VM's VPC network
  • Peering subnet routes in a peered VPC network
  • Routes in another network whose next hops are Cloud VPN tunnels, Cloud Interconnect (VLAN) attachments, or Router appliance VMs located in the receiving VM's VPC network

Destinations for packets that are routed within a VPC network include:

  • The primary internal IPv4 address of the receiving VM's network interface (vNIC). Primary internal IPv4 addresses are regional internal IPv4 addresses that come from a subnet's primary IPv4 address range.
  • An internal IPv4 address from an alias IP range of the receiving VM's vNIC. Alias IP ranges can come from either a subnet's primary IPv4 address range or one of its secondary IPv4 address ranges.
  • An IPv6 address from the /96 IPv6 address range assigned to a dual-stack receiving VM's vNIC. VM IPv6 ranges can come from these subnet IPv6 ranges:
  • An internal IPv4 address of a forwarding rule used by internal protocol forwarding to the receiving VM or internal passthrough Network Load Balancer where the receiving VM is a backend of the load balancer. Internal forwarding rule IPv4 addresses come from a subnet's primary IPv4 address range.
  • An internal IPv6 address from the /96 IPv6 range of a forwarding rule used by internal protocol forwarding to the receiving VM or internal passthrough Network Load Balancer where the receiving VM is a backend of the load balancer. Internal forwarding rule IPv6 addresses come from a subnet's internal IPv6 address range.
  • An external IPv6 address from the /96 IPv6 range of a forwarding rule used by external protocol forwarding to the receiving VM or external passthrough Network Load Balancer where the receiving VM is a backend of the load balancer when the incoming packet is routed within the VPC network using one of the routes listed previously in this section. External forwarding rule IPv6 addresses come from a subnet's external IPv6 address range.
  • An IP address within the destination range of a custom static route that uses the receiving VM as a next hop VM (next-hop-instance or next-hop-address).
  • An IP address within the destination range of a custom static route using an internal passthrough Network Load Balancer (next-hop-ilb) next hop, if the receiving VM is a backend for that load balancer.

Ingress to destinations outside of a VPC network

Google Cloud implements the following bandwidth restrictions for incoming packets delivered to a receiving VM using routes outside a VPC network. These bandwidth restrictions are applied individually to each receiving VM. The inbound bandwidth restriction that is applied is whichever of the following that is reached first:

  • 1,800,000 packets per second
  • 20 Gbps

Destinations for packets that are routed using routes outside of a VPC network include:

  • An external IPv4 address assigned in a one-to-one NAT access configuration on one of the receiving VM's network interfaces (NICs).
  • An external IPv6 address from the /96 IPv6 address range assigned to a vNIC of a dual-stack receiving VM when the incoming packet is routed using a route outside of the receiving VM's VPC network.
  • An external IPv4 address of a forwarding rule used by external protocol forwarding to the receiving VM or external passthrough Network Load Balancer where the receiving VM is a backend of the load balancer.
  • An external IPv6 address from the /96 IPv6 range of a forwarding rule used by external protocol forwarding to the receiving VM or external passthrough Network Load Balancer where the receiving VM is a backend of the load balancer when the incoming packet is routed using a route outside of a VPC network.
  • Established inbound responses processed by Cloud NAT

Jumbo frames

To receive and send jumbo frames, configure the VPC network used by your VMs; set the maximum transmission unit (MTU) to a larger value, up to 8896.

Higher MTU values increase the packet size and reduce the packet-header overhead, which increases payload data throughput.

To use jumbo frames with the gVNIC driver, you must use version 1.3 or later of the driver. Not all Google Cloud public images include this driver version. For more information about operating system support for jumbo frames, see the Networking features tab on the Operating system details page. The image versions that indicate full support for jumbo frames include the updated gVNIC driver, even if the guest OS shows the gve driver version as 1.0.0.

If you are using an OS image that doesn't have full support for jumbo frames, you can manually install gVNIC driver version v1.3.0 or later. Google recommends installing the gVNIC driver version marked Latest to benefit from additional features and bug fixes. You can download the gVNIC drivers from GitHub.

To manually update the gVNIC driver version in your guest OS, see Use on non-supported operating systems.

Receive and transmit queues

Each VM vNIC is assigned a number of receive and transmit queues for processing packets from the network.

  • Receive Queue (RX): Queue to receive packets. When the vNIC receives a packet from the network, the vNIC selects the descriptor for an incoming packet from the queue, processes it and hands the packet to the guest OS over a packet queue attached to a vCPU core using an interrupt. If the RX queue is full and there is no buffer available to place a packet, then the packet is dropped. This can typically happen if an application is over-utilizing a vCPU core that is also attached to the selected packet queue.
  • Transmit Queue (TX): Queue to transmit packets. When the guest OS sends a packet, a descriptor is allocated and placed in the TX queue. The vNIC then processes the descriptor and transmits the packet.

Default queue allocation

Unless you explicitly assign queue counts for NICs, you can model the algorithm Google Cloud uses to assign a fixed number of RX and TX queues per vNIC in this way:

  1. Use one of the following methods, depending on your network interface type:

    • VirtIO: Divide the number of vCPUs by the number of NICs, and discard any remainder —[number of vCPUs/number of NICs].
    • gVNIC: Divide the number of vCPUs by the number of NICs, and then divide the result by 2 and discard any remainder — `[number of vCPUs/number of NICs/2].

    This calculation always results in a whole number (not a fraction).

  2. If the calculated number is less than 1, assign each vNIC one queue instead.

  3. Determine if the calculated number is greater than the maximum number of queues per vNIC. The maximum number of queues per vNIC depends on the driver type:

    • Using virtIO or a custom driver, the maximum number of queues per vNIC is 32. If the calculated number is greater than 32, ignore the calculated number, and assign each vNIC 32 queues instead.
    • Using gVNIC, the maximum number of queues per vNIC is 16. If the calculated number is greater than 16, ignore the calculated number, and assign each vNIC 16 queues instead.

The following examples show how to calculate the default number of queues:

  • If a VM uses VirtIO and has 16 vCPUs and 4 NICs, the calculated number is [16/4] = 4. Google Cloud assigns each vNIC four queues.

  • If a VM using gVNIC and has 128 vCPUs and two NICs, the calculated number is [128/2/2] = 32. Google Cloud assigns each vNIC the maximum number of queues per vNIC possible. Google Cloud assigns 16 queues per vNIC.

On Linux systems, you can use ethtool to configure a vNIC with fewer queues than the number of queues Google Cloud assigns per vNIC.

Custom queue allocation

Instead of the Default queue allocation, you can assign a custom queue count (total of both RX and TX) to each vNIC when you create a new VM by using the Compute Engine API.

The number of custom queues you specify must adhere to the following rules:

  • The minimum queue count you can assign per vNIC is one.

  • The maximum queue count you can assign to each vNIC is the lower of the vCPU count or the per vNIC maximum queue count, based on the driver type:

    • Using virtIO or a custom driver, the maximum queue count is 32.
    • Using gVNIC, the maximum queue count is 16.

  • If you assign custom queue counts to all NICs of the VM, the sum of your queue count assignments must be less than or equal to the number of vCPUs assigned to the VM instance.

You can oversubscribe the custom queue count for your NICs. In other words, you can have a sum of the queue counts assigned to all NICs for your VM that is greater than the number of vCPUs for your VM. To oversubscribe the custom queue count, you must satisfy the following conditions:

  • You use gVNIC as the vNIC type for all NICs configured for the VM.
  • Your VM uses a machine type from the N2, N2D, C2 and C2D machine series.
  • You enabled Tier_1 networking for the VM.
  • You specified a custom queue count for all NICs configured for the VM.

With queue oversubscription, the maximum queue count for the VM is 16 times the number of NICs. So, if you have 6 NICs configured for a VM with 30 vCPUs, you can configure a maximum of (16 * 6), or 96 custom queues for your VM.

Examples

  • If a VM has 8 vCPUs and 3 NICs, the maximum queue count for the VM is the number of vCPUS, or 8. You can assign 1 queue to nic0, 4 queues to nic1, and 3 queues to nic2. In this example, you cannot subsequently assign 4 queues to nic2 while keeping the other two vNIC queue assignments because the sum of assigned queues cannot exceed the number of vCPUs (8).

  • If a VM has 96 vCPUs and 2 NICs, you can assign both NICs up to 32 queues each when using the virtIO driver, or up to 16 queues each when using the gVNIC driver. In this example, the sum of assigned queues is always less than the number of vCPUs.

It's also possible to assign a custom queue count for only some NICs, letting Google Cloud assign queues to the remaining NICs. The number of queues you can assign per vNIC is still subject to rules mentioned previously. You can model the feasibility of your configuration, and, if your configuration is possible, the number of queues that Google Cloud assigns to the remaining NICs with this process:

  1. Calculate the sum of queues for the NICs using custom queue assignment. For an example VM with 20 vCPUs and 6 NICs, suppose you assign nic0 5 queues, nic1 6 queues, nic2 4 queues, and let Google Cloud assign queues for nic3, nic4, and nic5. In this example, the sum of custom-assigned queues is 5+6+4 = 15.

  2. Subtract the sum of custom-assigned queues from the number of vCPUs. If the difference is not at least equal to the number of remaining NICs for which Google Cloud must assign queues, Google Cloud returns an error. Continuing with the example VM of 20 vCPUs and a sum of 15 custom-assigned queues, Google Cloud has 20-15 = 5 queues left to assign to the remaining NICs (nic3, nic4, nic5).

  3. Divide the difference from the previous step by the number of remaining NICs and discard any remainder —⌊(number of vCPUs - sum of assigned queues)/(number of remaining NICs)⌋. This calculation always results in a whole number (not a fraction) that is at least equal to one because of the constraint explained in the previous step. Google Cloud assigns each remaining NICs a queue count matching the calculated number as long as the calculated number is not greater than the maximum number of queues per vNIC. The maximum number of queues per vNIC depends on the driver type:

    • Using virtIO or a custom driver, if the calculated number of queues for each remaining vNIC is greater than 32, Google Cloud assigns each remaining vNIC 32 queues.
    • Using gVNIC, if the calculated number of queues for each remaining vNIC is greater than 16, Google Cloud assigns each remaining vNIC 16 queues.

Configure custom queue counts

To create a VM that uses a custom queue count for one or more vNICs, complete the following steps.

gcloud

  1. If you don't already have a VPC network with a subnet for each vNIC interface you plan to configure, create them.
  2. Use the gcloud compute instances create command to create the VM. Repeat the --network-interface flag for each vNIC you want to configure for the VM, and include the queue-count option.
    gcloud compute instances create VM_NAME \
        --zone=ZONE \
        --machine-type=MACHINE_TYPE \
        --network-performance-configs=total-egress-bandwidth-tier=TIER_1  \
        --network-interface=network=NETWORK_NAME_1,subnet=SUBNET_1,nic-type=GVNIC,queue-count=QUEUE_SIZE_1 \
        --network-interface=network=NETWORK_NAME_2,subnet=SUBNET_2,nic-type=GVNIC,queue-count=QUEUE_SIZE_2

Replace the following:

  • VM_NAME: a name for the new VM
  • ZONE: the zone to create the VM in
  • MACHINE_TYPE: the machine type of the VM. The machine type you specify must support gVNIC and Tier_1 networking.
  • NETWORK_NAME: the name of the network created previously
  • SUBNET_*: the name of one of the subnets created previously
  • QUEUE_SIZE: the number of queues for the vNIC, subject to the rules discussed in Custom queue allocation.

Terraform

  1. If you don't already have a VPC network with a subnet for each vNIC interface you plan to configure, create them.

  2. Create a VM with specific queue counts for vNICs using the google_compute_instance resource. Repeat the --network-interface parameter for each vNIC you want to configure for the VM, and include the queue-count parameter.

    # Queue oversubscription instance
resource "google_compute_instance" "VM_NAME" {
project      = "PROJECT_ID"
boot_disk {
  auto_delete = true
  device_name = "DEVICE_NAME"
  initialize_params {
     image="IMAGE_NAME"
     size = DISK_SIZE
     type = "DISK_TYPE"
  }
}
machine_type = "MACHINE_TYPE"
name         = "VM_NAME"
zone = "ZONE"

network_performance_config {
    total_egress_bandwidth_tier = "TIER_1"
}

network_interface {
    nic_type = "GVNIC"
    queue_count = QUEUE_COUNT_1
    subnetwork_project = "PROJECT_ID"
    subnetwork = "SUBNET_1"
 }

network_interface {
    nic_type = "GVNIC"
    queue_count = QUEUE_COUNT_2
    subnetwork_project = "PROJECT_ID"
    subnetwork = "SUBNET_2"
}

network_interface {
    nic_type = "GVNIC"
    queue_count = QUEUE_COUNT_3
    subnetwork_project = "PROJECT_ID"
    subnetwork = "SUBNET_3""
}

network_interface {
    nic_type = "GVNIC"
    queue_count = QUEUE_COUNT_4
    subnetwork_project = "PROJECT_ID"
    subnetwork = "SUBNET_4""
}

}

Replace the following:

  • VM_NAME: a name for the new VM
  • PROJECT_ID: ID of the project to create the VM in. Unless you are using a Shared VPC network, the project you specify must be the same one in which all the subnets and networks were created in.
  • DEVICE_NAME: The name to associate with the boot disk in the guest OS
  • IMAGE_NAME: the name of an image,for example, "projects/debian-cloud/global/images/debian-11-bullseye-v20231010".
  • DISK_SIZE: the size of the boot disk, in GiB
  • DISK_TYPE: the type of disk to use for the boot disk, for example, pd-standard
  • MACHINE_TYPE: the machine type of the VM. The machine type you specify must support gVNIC and Tier_1 networking.
  • ZONE: the zone to create the VM in
  • QUEUE_COUNT: the number of queues for the vNIC, subject to the rules discussed in Custom queue allocation.
  • SUBNET_*: the name of the subnet that the network interface connects to

REST

  1. If you don't already have a VPC network with a subnet for each vNIC interface you plan to configure, create them.

  2. Create a VM with specific queue counts for NICs using the instances.insert method. Repeat the networkInterfaces property to configure multiple network interfaces.

    POST https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/zones/ZONE/instances
{
"name": "VM_NAME",
"machineType": "machineTypes/MACHINE_TYPE",
"networkPerformanceConfig": {
    "totalEgressBandwidthTier": TIER_1
},
"networkInterfaces": [
    {
      "nicType": gVNIC,
      "subnetwork":"regions/region/subnetworks/SUBNET_1",
      "queueCount": "QUEUE_COUNT_1"
    } ],
"networkInterfaces": [
    {
      "nicType": gVNIC,
      "subnetwork":"regions/region/subnetworks/SUBNET_2",
      "queueCount": "QUEUE_COUNT_2"
    } ],
}

    Replace the following:

    • PROJECT_ID: ID of the project to create the VM in
    • ZONE: zone to create the VM in
    • VM_NAME: name of the new VM
    • MACHINE_TYPE: machine type, predefined or custom, for the new VM
    • SUBNET_*: the name of the subnet that the network interface connects to
    • QUEUE_COUNT: Number of queues for the vNIC, subject to the rules discussed in Custom queue allocation.

Queue allocations and changing the machine type

VMs are created with a default queue allocation, or you can assign a custom queue count to each virtual network interface card (vNIC) when you create a new VM by using the Compute Engine API. The default or custom vNIC queue assignments are only set when creating a VM. If your VM has vNICs which use default queue counts, you can change its machine type. If the machine type that you are changing to has a different number of vCPUs, the default queue counts for your VM are recalculated based on the new machine type.

If your VM has vNICs which use custom, non-default queue counts, you can change the machine type by using the Google Cloud CLI or Compute Engine API to update the instance properties. The conversion succeeds if the resulting VM supports the same queue count per vNIC as the original VM. For VMs that use the VirtIO-Net interface and have a custom queue count that is higher than 16 per vNIC, you can't change the machine type to a third generation machine type, which uses only gVNIC. Instead, you can migrate your VM to a third generation machine type by following the instructions in Migrate your workload from an existing VM to a new VM.

What's next