add hard limit for http client connection#91016
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Pull request overview
This PR adds hard limit configurations for HTTP client connections across three connection groups (disk, storage, and http). When the hard limit is reached, an exception is thrown instead of allowing further connection creation.
- Added
hard_limitfield to connection pool limits configuration - Implemented hard limit checking before connection creation with appropriate error handling
- Added test coverage for the new hard limit functionality
Reviewed changes
Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.
Show a summary per file
| File | Description |
|---|---|
| src/Core/ServerSettings.cpp | Added three new server settings for hard limits (disk_connections_hard_limit, storage_connections_hard_limit, http_connections_hard_limit) with default values and reduced disk_connections_store_limit |
| src/Common/HTTPConnectionPool.h | Added hard_limit field to the Limits struct with default value of 25000 |
| src/Common/HTTPConnectionPool.cpp | Implemented hard limit check in prepareNewConnection method and added new error code HTTP_CONNECTION_LIMIT_REACHED |
| src/Common/ErrorCodes.cpp | Registered new error code HTTP_CONNECTION_LIMIT_REACHED (762) |
| programs/server/Server.cpp | Wired up the new hard limit settings to HTTPConnectionPools initialization |
| src/Common/tests/gtest_connection_pool.cpp | Renamed existing HardLimit test to StoreLimit and added new HardLimit test to verify exception throwing behavior |
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Workflow [PR], commit [5f719f0] Summary: ❌
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Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
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Please write the changelog entry
src/Core/ServerSettings.cpp
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| DECLARE(UInt64, disk_connections_warn_limit, 10000, R"(Warning massages are written to the logs if number of in-use connections are higher than this limit. The limit applies to the disks connections.)", 0) \ | ||
| DECLARE(UInt64, disk_connections_store_limit, 30000, R"(Connections above this limit reset after use. Set to 0 to turn connection cache off. The limit applies to the disks connections.)", 0) \ | ||
| DECLARE(UInt64, disk_connections_store_limit, 15000, R"(Connections above this limit reset after use. Set to 0 to turn connection cache off. The limit applies to the disks connections.)", 0) \ | ||
| DECLARE(UInt64, disk_connections_hard_limit, 25000, R"(Exception is thrown at a creation attempt when this limit is reached. Set to 0 to turn off hard limitation. The limit applies to the disks connections.)", 0) \ |
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Cherry pick #91016 to 25.11: add hard limit for http client connection
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Backport #91016 to 25.11: add hard limit for http client connection
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Changelog entry (a user-readable short description of the changes that goes into CHANGELOG.md):
Now
HTTP_CONNECTION_LIMIT_REACHEDexception would be thrown whenhard_limitfor the http clients connection is reached. It is set as20000for the disk connections.Documentation entry for user-facing changes