This repository has been archived by the owner on Jan 26, 2024. It is now read-only.
SetTag when span finish #129
Open
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to subscribe to this conversation on GitHub.
Already have an account?
Sign in.
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
In my practice, I find that sometimes Tags may need be set at span finish. For example, tracer has a 1/1000 sampler so not every span needs to be reported to backend. SetTag in StartSpan is wasteful when not hitting. Only at Finish，tracer can fully determine if it needs to report span because only at Finish tracer can know whether RPC was successful or not， and failed RPC will also lead to span reporting.
SetTag when span finish can help making interface more flexible and reducing useless operations. If span does not need to be reported, just do not SetTag, this judgment needs to be put in Finish.
In my experiment, an echo server has 50% performance improvement if using this change.