HTTP/2 Upload speed issue compared to HTTP/1.1

Olivier HOUSSIN 1 Reputation point
2020-10-26T08:57:37.74+00:00

Hi all,

When I switch my WebApp to HTTP/2.0, the upload speed is decreased by about 30% compared to HTTP/1.1, it seems that this is the same case as CloudFare encounter some week ago: https://blog.cloudflare.com/delivering-http-2-upload-speed-improvements/

Does anyone know how to get rid of it?

Thanks in advance

Azure App Service
Azure App Service
Azure App Service is a service used to create and deploy scalable, mission-critical web apps.
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  1. Ryan Hill 28,636 Reputation points Microsoft Employee
    2021-01-22T16:00:40.477+00:00

    We have determined the root cause of the decreased upload speed is due to the Flow Control window of HTTP/2 which is defaulted at 65535 bytes. We have taken up a work item to increase the default Flow Control Window size. Validation will need to happen to ensure there are no negative impacts. Therefore, there will be considerable time before any changes are rolled out.

    Regards,
    Ryan

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