Web性能回归检测（第2部分）

Michelle Vu | Web Performance Engineer;

Michelle Vu | 网络性能工程师；

Fighting regressions has been a priority at Pinterest for many years. In part one of this article series, we provided an overview of the performance program at Pinterest. In this second part, we discuss how we monitor and investigate regressions in our Pinner Wait Time and Core Web Vital metrics for desktop and mobile web using real time metrics from real users. These real time graphs have been invaluable for regression alerting and root cause analysis.

多年来，解决回归问题一直是Pinterest的重点。在本系列文章的第一部分中，我们概述了Pinterest的性能计划。在本文的第二部分中，我们讨论了如何使用来自真实用户的实时指标监控和调查桌面和移动Web的Pinner等待时间和核心Web关键指标的回归。这些实时图表对于回归警报和根本原因分析非常宝贵。

Alerts

警报

Previously, our alerts and Jira tickets were based on a seven day moving average based on daily aggregations. Migrating our alerts and regression investigation process to be based on our real time graphs paved the way for faster resolution on regressions for a few reasons:

以前，我们的警报和Jira工单是基于每天聚合的七天移动平均值。将我们的警报和回归调查流程迁移到基于实时图表的方式为以下几个原因加快了回归问题的解决：

1. Immediately available data with more granular time intervals means regressions are detected more quickly and accurately.
2. 更细粒度的即时可用数据意味着可以更快、更准确地检测到回归。

• More granular time intervals allow us to see spikes more clearly, as they typically occur over the short time span it takes for an internal change to rollout (usually less than 30 minutes).
• 更精细的时间间隔使我们能够更清楚地看到峰值，因为它们通常发生在内部更改推出的短时间内（通常不到30分钟）。
• Additionally, regressions are easier to detect when the previous two weeks of data is used as a comparison baseline. Spikes and dips from normal daily and weekly patterns will not trigger alerts, as the delta between the current value and the previous weeks doesn’t change. An alert only triggers when a regression spikes beyond the max value from the previous two weeks for that same time of day and day of the week. Warning alerts are triggered after the regression is sustained for 30 minutes, while critical alerts accompanied by a Jira ticket are triggered after the regression is sustained for several hours.
• 此外，当使用前...