# Objective

- Reduce excessive RAM usage during long agent sessions. Previously
every
`Thread::notify` triggered a full serialization of the entire
conversation
(including any embedded base64 image) to JSON, so streaming bursts
queued
many large, redundant saves and ballooned memory into the multi-GB
range.
- Related to #57126.
- Related to #62133.

## Solution

- Replace the per-notification save task with a single coalescing save
worker
  per session in `crates/agent/src/agent.rs`.
- `save_thread` now writes the latest snapshot into an in-place buffer
and wakes
  the worker via a `watch` channel, instead of spawning a fresh
  full-conversation save on every notification.
- The worker drains the buffer in a loop, saving only the latest
snapshot per
burst (latest-wins coalescing), and preserves save-on-close by draining
the
  final snapshot before exiting.

## Testing

- `cargo check -p agent`
- `cargo test -p agent test_close_session_saves_thread`
- `cargo test -p agent test_save_load_thread`
- `cargo test -p agent test_threads_flushed_to_database_on_app_quit`

## Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [x] Unsafe blocks (if any) have justifying comments
- [x] The content adheres to Zed's UI standards (no UI change)
- [x] Tests cover the new/changed behavior
- [x] Performance impact has been considered and is acceptable

---

Release Notes:

- Improved memory usage during long agent sessions.

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Co-authored-by: Kirill Bulatov <kirill@zed.dev>