https://sap.github.io/spartacus-docs/server-side-rendering-optimization/
为什么要引入服务器端渲染优化？
Without SSR optimization, it is possible for the following to occur:
Pages do not render quickly enough, which leads to SSR using too much memory, and eventually it fails.
如果页面渲染不够快，可能会导致 SSR 使用了太多内存，最终导致渲染失败；
A response is not received in time, and an HTTP 500 error is returned.
无法按时接收到响应，只得返回 HTTP 500 错误给客户端。
SSR 优化引擎的参数
timeout
a number that indicates the amount of time (in milliseconds) during which the SSR server tries to render a page, before falling back to CSR.
该配置的单位是毫秒，代表 SSR 服务器在退化到使用客户端渲染之前，能够消耗用于渲染页面的时间。如果过了这个时间间隔，还未完成服务器端渲染，则返回 CSR 的 index.html 给客户端。该 index.html 不包含任何渲染好的 markup.
