Hello @Gao, Aimee Xiaomei
Burstable (B-series) compute tier is designed for workloads that do not require the full performance of the CPU continuously. The B-series provides you with the ability to purchase a VM size with baseline performance and the VM instance builds up credits when it is using less than its baseline. When the VM has accumulated credit, it can burst above the baseline using up to 100% of the CPU when your application requires higher CPU performance. If the VM is started/stopped or restarted, the credits may be lost. For more information, see below https://learn.microsoft.com/en-us/azure/virtual-machines/b-series-cpu-credit-model/b-series-cpu-credit-modelhttps://azure.microsoft.com/en-us/pricing/details/virtual-machines/windows/?msockid=0b10324aa7cf6f682a2226caa69d6e77#pricing
Hope this helps! If you have any further questions, tag me in the comments.
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