You are monitoring a service that uses n2-standard-2 Compute Engine instances that serve large files. Users have reported that downloads are slow. Your Cloud Monitoring dashboard shows that your VMs…

Adding additional network interface controllers (NICs) generally provides more network interfaces for isolation or routing, but it does not increase the maximum network throughput of a single VM instance beyond its machine type's limit.

A Cloud NAT gateway is used for outbound internet connectivity for private instances and does not improve the internal network throughput performance of a VM serving files or its egress bandwidth.

The n2-standard machine types have increasing network bandwidth limits as the number of vCPUs increases. An n2-standard-2 (2 vCPUs) has a lower network throughput limit compared to an n2-standard-8 (8 vCPUs), which offers significantly higher egress bandwidth, directly addressing the observed bottleneck of "peak network throughput."

Deploying the Ops Agent exports more monitoring metrics but does not address or improve the underlying network throughput performance of the VM itself.