Investigate startup performance regression

[bpasero]

It seems that the exploration builds run slower. One theory is that maybe the disabled script streaming has an impact (this was needed to unblock sandbox working on Linux when running out of sources). Should validate if we actually load multiple scripts on startup that could now result in a waterfall without script streaming.

[bpasero]

Does not look so good:

I suggest to see if script streaming enabled on Windows helps.

[deepak1556]

Numbers on my local setup are not bad, although it is not 1:1 same setup as our perf bot since the bot runs the application as a service.

Stable 1.70.0

2343	Code	da76f93349	90e9a697-6490-41bd-a634-3a8dda36c4e41660050399473	NO_standard_start : Active editor is not a text editor
2008	Code	da76f93349	25b69d3a-e6a7-4a20-a43f-52318a06bf591660050427835	standard_start
1931	Code	da76f93349	c6a864db-6f51-4ea1-83d2-fd9acf80a03d1660050456743	standard_start
1962	Code	da76f93349	bff11f60-4f92-4f7a-94e6-1327302eb51e1660050490998	standard_start
1794	Code	da76f93349	f87d602d-7d18-4bbd-b7a0-ab53f31abac11660050519246	standard_start
1925	Code	da76f93349	3cc5e206-467f-43e3-9f1b-1536025a23701660050547070	standard_start
1985	Code	da76f93349	8e9aa434-fec4-4695-8cb5-7f868c5250911660050599940	standard_start

Insiders 1.71.0

2959	Code - Insiders	fe946068ba	4581ba9d-0ce0-423a-96b3-eb0352ec68961660057514331	NO_standard_start : Either cache data is rejected or not created
2178	Code - Insiders	fe946068ba	2de8372d-8419-4364-a18b-0596750fa9421660057554711	standard_start
2110	Code - Insiders	fe946068ba	43e1ba77-5eac-4fef-bedc-029d700be3b01660057583477	standard_start
2016	Code - Insiders	fe946068ba	53c18005-0912-479c-8166-374b3de846a21660057612731	standard_start
2052	Code - Insiders	fe946068ba	6827c41b-c5ea-4117-828a-b60ccc070ffe1660057642634	standard_start
2072	Code - Insiders	fe946068ba	4dc8dd13-2d24-43a6-bb21-f1bac0dda3101660057674277	standard_start
1823	Code - Insiders	fe946068ba	819c84da-4a7c-49a9-a525-a600f2e46b141660057702658	standard_start

[deepak1556]

Also, confirmed that script streaming is enabled in Electron 19 with current Insiders. Chrome trace with script streaming enabled and disabled shows it does not impact workbench load for product builds.

I will add some steps below to collect some relevant traces from the perf bot for further debugging.

[bpasero]

Thanks, just from the numbers it does look like for you 1.71.0 overall executes slower. To drill in we would probably have to check the numbers from the performance editor to see if there is a specific thing.

Btw will also try with my Surface Laptop once I am in the office and once it arrived.

To clarify: script streaming was just enabled for testing or are we generally back to script streaming?

[deepak1556]

script streaming was just enabled for testing or are we generally back to script streaming ?

It is enabled by default in Electron 19 since the update made to main branch.

To drill in we would probably have to check the numbers from the performance editor to see if there is a specific thing.

Yeah let me check on that.

[deepak1556]

Couple of traces that would help from the perf bot once @jrieken gets back from vacation,

1. For both stable and insiders separately, to get chrome startup trace start the application with --trace-startup --trace-startup-duration=20 --trace-startup-file=<absolute-path-to>/chrometrace.log, once the application is exited the trace will be generated at the location specified.

2. For both stable and insiders separately, to get windows performance trace (ETW)

• Open Windows Performance Recorder from system start menu
• Have the following settings

• Start the recorder
• Open the application
• Once the application has completely loaded, stop the recorder and save the profile
• Send the profile to Deepak.Mohan@microsoft.com since it will contain sensitive information.

[bpasero]

Fyi summary of my experiments:

• cannot reproduce a slowdown on my new Surface Laptop 3 with Windows 11 [1]
• running exploration build on the perf bot
  • same slowness when going back to Electron 18
  • same slowness when disabling sandbox and utility process

[1] Setup:

• simple TS project, package.json opened
• startup perf editor in second column
• same startup CLI flags as perf bot
• looking for workbench ready numbers