Parallelize RegistryToolLoader initialization for faster startup#1534
Merged
g2vinay merged 4 commits intomicrosoft:mainfrom Jan 27, 2026
Merged
Conversation
g2vinay
requested review from
JonathanCrd,
chidozieononiwu,
Copilot,
jongio,
joshfree,
msalaman,
vukelich and
wbreza
Contributor
There was a problem hiding this comment.
Pull request overview
Improves Azure MCP Server startup performance by parallelizing external MCP server/client initialization in RegistryToolLoader and adding diagnostics/timing to help identify startup delays.
Changes:
- Parallelized registry-discovered server initialization using
Task.WhenAll. - Added initialization timing + summary logs (server count, success count, tool count, elapsed time).
- Added a changelog entry describing the performance improvement.
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.
| File | Description |
|---|---|
| servers/Azure.Mcp.Server/changelog-entries/1769471477283.yaml | Documents the startup performance improvement. |
| core/Azure.Mcp.Core/src/Areas/Server/Commands/ToolLoading/RegistryToolLoader.cs | Initializes MCP clients/tools in parallel and logs timing/summary metrics. |
…allelize-registry-tool-loader-initialization
anuchandy
approved these changes
Jan 27, 2026
Member
anuchandy
left a comment
anuchandy
left a comment
There was a problem hiding this comment.
Thanks, Vinay - just 2 minor comments for your review.
anuchandy
approved these changes
Jan 27, 2026
github-project-automation
Bot
moved this from Untriaged
to In Progress
in Azure MCP Server
colbytimm
pushed a commit
to colbytimm/microsoft-mcp
that referenced
this pull request
Apr 20, 2026
This file contains hidden or 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 join this conversation on GitHub.
Already have an account?
Sign in to comment
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.
Resolves #1026
perf: Parallelize RegistryToolLoader initialization to reduce startup time
This change addresses a ~20 second startup delay when running the Azure MCP
Server in VS Code via the VSIX extension.
Problem:
The RegistryToolLoader was sequentially initializing 47 MCP server processes
(one for each Azure service command group). With each server taking ~400-500ms
to start, the cumulative delay was 20+ seconds.
Change:
Performance Improvement:
The diagnostic logs now show: