Hi @rainbow_guy
Thank you for reaching out to Microsoft Q&A Platform .
Regarding your question all the B series VM's doesn't have an network bandwidth benchmark as this size is suggested only for development/testing purpose .
You can just compare the benchmarks here as an example:
https://learn.microsoft.com/en-us/azure/virtual-machines/sizes-b-series-burstable
https://learn.microsoft.com/en-us/azure/virtual-machines/dv2-dsv2-series
So it would be really difficult to suggest any improvements for the variable network performance .
For testing purpose , Please do try out another VM size and test your use case . If you still see some issues then , try to run a quick perfinsights report on the VM for more insights:
https://learn.microsoft.com/en-us/troubleshoot/azure/virtual-machines/performance-diagnostics
Hope this provides you some direction .
Thanks & Regards,
Pradeep
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