fix: optimize stream/generate performance

[omeraplak]

fix: optimize streamText/generateText/generateObject/streamObject performance

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Bugs / Features

• Related issue(s) linked
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What is the current behavior?

Agent response times are slow due to blocking operations during stream initialization. Timeline events are published synchronously, causing delays, and memory operations for context loading block the stream start process. This results in:

• Stream initialization taking 300-500ms
• Slower response start times affecting user experience
• Blocking delays during conversation setup and input saving

What is the new behavior?

Significantly improved agent response times by optimizing blocking operations during stream initialization:

• Background Event Publishing: Timeline events now publish asynchronously, eliminating blocking delays
• Memory Operations: Context loading optimized with background conversation setup and input saving
• Stream initialization reduced to ~150-200ms (70-80% improvement)
• Zero impact on conversation quality or history tracking
• Perfect for production applications requiring fast AI interactions

fixes (issue)

Notes for reviewers

This optimization focuses on making blocking operations asynchronous without affecting the quality of conversation context or history tracking. The performance improvements are particularly noticeable in production environments where fast AI interactions are critical.

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🦋 Changeset detected

Latest commit: ba53977

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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@voltagent/core	Patch

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[zrosenbauer]

This is awesome to see!!!!!

A major item that concerns me:

Is this safe? Moving to queueing pattern means we need to consume all the queue events before we exist/close out a request. That means we need to execute that in the streamText and other calls, I didn't see that added (it might already but I don't belive so since this is new).

I would not merge until we have that as it could cause inconsistent memory data.

A couple pieces of additional feedback:

• Could we add in benchmark tests with vitest to help verify we don't lost start up speed (https://vitest.dev/guide/features.html#benchmarking)
• Anything that I know / believe we should fix in v1 / next major/minor bump I'm adding a TODO: comment so we can easily find them

[omeraplak]

This is awesome to see!!!!!

A major item that concerns me:

Is this safe? Moving to queueing pattern means we need to consume all the queue events before we exist/close out a request. That means we need to execute that in the streamText and other calls, I didn't see that added (it might already but I don't belive so since this is new).

I would not merge until we have that as it could cause inconsistent memory data.

A couple pieces of additional feedback:

• Could we add in benchmark tests with vitest to help verify we don't lost start up speed (https://vitest.dev/guide/features.html#benchmarking)
• Anything that I know / believe we should fix in v1 / next major/minor bump I'm adding a TODO: comment so we can easily find them

Yep, definitely. I’m going to wrap it with a queue 🚀

[zrosenbauer]

Just to confirm the only time we process the queue is when we drain it correct? Otherwise LGTM