PriorityBucket

Page load time is a web performance metric that directly impacts user experience. It measures the time it takes to fully load a web page after making a request. However, as the first visual feedback of a web page, first rendering time is also a key metric to satisfy the users. In this paper, we focus on speeding up the first rendering time in page loading from the perspective of protocol improvements. We observe that by prioritizing the streams that make up the critical rendering path in Multipath-QUIC (MPQUIC), the first rendering time can be effectively reduced. Therefore, we propose PriorityBucket - an MPQUIC scheduler that provides stream prioritization in the transport layer. By comparing to the existing schedulers of MPQUIC, we show its effectiveness in reducing the first rendering time and page load time of web pages in different path heterogeneity using the Chrome browser. Results show that PriorityBucket can reduce the first rendering time and page load time up to 34% and 35% respectively in high path heterogeneity when loading Bing.