“系统"有什么作用?Chrome 时间线分析工具中的记录类别是什么意思? [英] What does the "System" category of records mean in Chrome Timeline profiling tool?

问题描述

我试图了解如何通过分析 Chrome 开发者工具中的时间轴数据来提高 D3.js 应用程序(数据的交互式可视化)的速度.

I'm trying to understand how the speed of a D3.js application (an interactive visualisation of data) could be improved by analysing the Timeline data in Chrome Developer Tool.

我正在拖动数据栏，它们在 mousemove 事件上被移动(SVG 转换).

I'm dragging the data bars around, them being moved (SVG transformations) on mousemove events.

时间轴告诉我，系统"进程使用了​​ 50% 的 CPU 时间(其余为脚本"、渲染"、绘制"和空闲").

Timeline tells me that 50% of CPU time is being used by "System" processes (the rest being "Scripting", "Rendering", "Painting", and "Idle").

系统"究竟是什么，如果需要 50% 的时间，可能会出现什么问题?

What exactly is "System", and what could be the problem, if it takes 50% of time?

顺便说一句，如果我通过按住鼠标右键而不是左键拖动，响应会好得多，而系统"仅使用大约 20% 的时间.

By the way, if I'm dragging by holding the right mouse button not left, the response is much better, and "System" uses only about 20% of time.

2020 年注意:在旧版 Chrome 中，系统"类别被命名为其他".

2020 note: in old Chrome the "System" category was named "Other".

推荐答案

两年前我问过我同样的问题.我不知道 System 类别分别代表什么灰色条.

I asked me the same question two years ago. I didn't know what the grey bars respectively the System category stand for.

很难找到官方答案，因为 Chrome DevTools Docs 只说未由 DevTools 检测的活动".但此声明已被删除，因为有一个 新文档.

It was hard to find an official answer because the only thing the Chrome DevTools Docs said was "Activity that was not instrumented by DevTools". But this statement was removed since there is a new documentation.

一些有用的信息:Chrome 开发工具:时间轴 - 白条

所以我查看了 Chromium 项目并搜索了 devtools 代码以获得答案.我发现 System 类别包含所有不属于 Loading、Scripting、Rendering、绘画和GPU:参见所有记录类型的列表.

So I checked out the Chromium project and searched the devtools code for an answer. I found out that the System category contains all activities that not belonging to the categories Loading, Scripting, Rendering, Painting and GPU: see the list of all record types.

根据 Chromium 源的另一个片段 将类型分配给类别我们可以看到时间轴将所有未分配或分配给系统类别的记录类型显示为灰色条在系统类别中:

Filtering this list against another fragment of Chromium's source that assigns types to categories we can see Timeline shows all record types that are unassigned or are assigned to the System category as grey bars in the System category:

• 激活图层树
• 提交加载
• CPU 配置文件
• DecodeLazyPixelRef
• DisplayItemListSnapshot
• DrawLazyPixelRef
• ImplSideFling
• InputLatencyMouseMove
• InputLatencyMouseWheel
• JS示例
• 添加了 JitCode
• JitCodeMoved
• 延迟信息流
• LayerTreeHostImplSnapshot
• LayoutInvalidationTracking
• LazyPixelRef
• MarkLCPInvalidate
• NeedsBeginFrameChanged
• 图片快照
• 个人资料
• 计划
• 光栅化
• ResourceMarkAsCached
• ScheduleStyleInvalidationTracking
• SetLayerTreeId
• StreamingCompileScript
• StyleInvalidatorInvalidationTracking
• StyleRecalcInvalidationTracking
• 任务
• TracingSessionIdForWorker
• TracingStartedInPage
• 更新计数器
• V8 执行
• V8 示例

2020 年注意:在旧版 Chrome 中，系统"类别被命名为其他".

2020 note: in old Chrome the "System" category was named "Other".

这篇关于“系统"有什么作用?Chrome 时间线分析工具中的记录类别是什么意思?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！