Eric Allam
45527e317a
## Summary Under high OTLP ingest volume, the whole decode, transform, and enrich pipeline runs on the request event loop, so a single CPU core becomes the ceiling while the rest sit idle. This adds an opt-in worker pool that moves decode, transform, and LLM-cost enrichment onto worker threads, keeping the main thread free for I/O. It is off by default (`OTEL_TRANSFORM_WORKER_POOL_ENABLED`), so behavior is unchanged unless enabled. ## Design Workers do decode, filter, convert, and enrich (including LLM pricing match). The main thread stays the single database reader: it loads the pricing registry and broadcasts the compiled model rows to the workers (re-broadcasting on every reload), so workers never touch the database. The pure transform is extracted into a dependency-light module (no Prisma/Redis/ClickHouse imports) so it can run inside a worker. Importantly, the main thread keeps the existing single consolidated insert path, so ClickHouse insert batching and part count are unchanged. The parallelism buys CPU headroom, not more insert streams (which would add merge pressure). The worker is bundled as a standalone file at build time and ships in the existing image with no Dockerfile change. In local load testing the pool sustained roughly 2.6x the throughput of the single-thread path and kept the main thread responsive under load.
Server Changes
This directory tracks changes to server-only components (webapp, supervisor, etc.) that are not captured by changesets. Changesets only track published npm packages — server changes would otherwise go undocumented.
When to add a file
Server-only PRs: If your PR only changes apps/webapp/, apps/supervisor/, or other server components (and does NOT change anything in packages/), add a .server-changes/ file.
Mixed PRs (both packages and server): Just add a changeset as usual. No .server-changes/ file needed — the changeset covers it.
Package-only PRs: Just add a changeset as usual.
File format
Create a markdown file with a descriptive name:
.server-changes/fix-batch-queue-stalls.md
With this format:
---
area: webapp
type: fix
---
Speed up batch queue processing by removing stalls and fixing retry race
Fields
- area (required):
webapp|supervisor - type (required):
feature|fix|improvement|breaking
Description
The body text (below the frontmatter) is a one-line description of the change. Keep it concise — it will appear in release notes.
Writing guidance
These entries are public-facing - they ship verbatim in user-visible release notes. A few rules to keep them clean:
- Write for the user, not the reviewer. Lead with what the user notices or has to do. If a reader who doesn't know the codebase can't tell what changed for them, rewrite it.
- One sentence is usually enough. The body is the bullet in the changelog. If you need a paragraph, you're probably describing the implementation rather than the change.
- Describe behavior, not implementation. Skip internal scopes, middleware names, library specifics, framework internals. Users care about what's different for them, not how it's wired.
- Never name internal tools or infra. Observability stacks, internal services, infra components, monitoring backends, CI surfaces, AWS specifics - none of these belong in user-facing notes.
Before / after:
- ❌ "The image verification step now parses the manifest's layer media types and returns a new result the finalizer rejects." (describes the wiring; a user can't act on it)
- ✅ "Deploying with an outdated CLI could produce an image that fails to start on every run. These deploys are now stopped before going live, with a message asking you to upgrade the CLI and re-deploy." (what the user sees and does)
Lifecycle
- Engineer adds a
.server-changes/file in their PR - Files accumulate on
mainas PRs merge - The changeset release PR includes these in its summary
- After the release merges, CI cleans up the consumed files
Examples
New feature:
---
area: webapp
type: feature
---
TRQL query language and the Query page
Bug fix:
---
area: webapp
type: fix
---
Fix schedule limit counting for orgs with custom limits
Improvement:
---
area: webapp
type: improvement
---
Use the replica for API auth queries to reduce primary load