[Internal] PPAF: Adds Dynamic Enablement of PPAF#5310
Merged
FabianMeiswinkel merged 29 commits intomasterfrom Aug 13, 2025
Merged
[Internal] PPAF: Adds Dynamic Enablement of PPAF#5310FabianMeiswinkel merged 29 commits intomasterfrom
FabianMeiswinkel merged 29 commits intomasterfrom
Conversation
NaluTripician
requested review from
adityasa,
khdang,
neildsh and
sboshra
as code owners
NaluTripician
requested review from
FabianMeiswinkel,
Pilchie,
kirankumarkolli and
kirillg
as code owners
ensures methods return false when PPAF is disabled
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
ananth7592
previously approved these changes
Aug 8, 2025
FabianMeiswinkel
previously approved these changes
Aug 11, 2025
Member
FabianMeiswinkel
left a comment
FabianMeiswinkel
left a comment
There was a problem hiding this comment.
LGTM except for one small question
NaluTripician
dismissed stale reviews from FabianMeiswinkel and ananth7592
via
da3ff36
FabianMeiswinkel
requested changes
Aug 12, 2025
Member
FabianMeiswinkel
left a comment
FabianMeiswinkel
left a comment
There was a problem hiding this comment.
LGTM except for the regex compilation comment
ananth7592
approved these changes
Aug 12, 2025
kundadebdatta
changed the title
NaluTripician
added
auto-merge
ananth7592
added a commit
that referenced
this pull request
May 1, 2026
…ind PPAF When ExcludeRegions filters out all preferred read regions and PPAF (Partition Level Failover) is enabled, GetApplicableEndpoints now falls back to WriteEndpoints[0] (dynamic, tracks current write region) instead of this.defaultEndpoint (static, region-agnostic URI set once at init). The fix is gated behind isPartitionLevelFailoverEnabled (Func<bool>) wired from ConnectionPolicy.EnablePartitionLevelFailover through GlobalEndpointManager, supporting dynamic enablement per PR #5310. When PPAF is disabled, original behavior (defaultEndpoint fallback) is preserved. Fixes #5821 Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
ananth7592
added a commit
that referenced
this pull request
May 4, 2026
… enabled and all regions excluded (#5823) ## Problem When ApplicationPreferredRegions == ExcludeRegions, LocationCache.GetApplicableEndpoints falls back to his.defaultEndpoint — a static, region-agnostic URI set once at init and never updated. After a write region (hub) switch, the GlobalAddressResolver's cached EndpointCache for this default endpoint has a stale AddressResolver.location, causing incorrect region tracking in diagnostics, per-partition routing, and retry logic. ## Fix When PPAF (IsPartitionLevelFailoverEnabled) is enabled, GetApplicableEndpoints now uses WriteEndpoints[0] (dynamic, tracks current write region) as the read fallback instead of his.defaultEndpoint. This aligns with: - UpdateLocationCache (L756-760) which already uses WriteEndpoints[0] for ReadEndpoints fallback - Java SDK: writeRegionalRoutingContexts.get(0) - Python SDK: get_write_regional_routing_contexts()[0] ### PPAF Gating The fix is gated behind Func<bool> isPartitionLevelFailoverEnabled wired from ConnectionPolicy.EnablePartitionLevelFailover through GlobalEndpointManager, supporting dynamic enablement per PR #5310. When PPAF is disabled, original behavior (defaultEndpoint fallback) is preserved. ## Changes - **LocationCache.cs**: Added isPartitionLevelFailoverEnabled parameter; gated read fallback behind it - **GlobalEndpointManager.cs**: Wires ConnectionPolicy.EnablePartitionLevelFailover into LocationCache - **LocationCacheTests.cs**: 3 new tests covering PPAF on/off/dynamic toggle scenarios ## Testing All 94 LocationCacheTests pass. Fixes #5821 --------- Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: Debdatta Kunda <87335885+kundadebdatta@users.noreply.github.com>
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.
Pull Request Template
Description
This pull request introduces enhancements to the partition-level failover (PPAF) functionality in the Azure Cosmos SDK. The changes include the addition of a default cross-region hedging strategy, dynamic enablement of PPAF based on the database account configuration without a restart of the SDK client, and new tests to validate these behaviors. Below are the most important changes grouped by theme:
Enhancements to Availability Strategy:
SDKDefaultCrossRegionHedgingStrategyinAvailabilityStrategy.csto provide a default hedging strategy for cross-region failover, including support for write requests on multi-region accounts.IsSDKDefaultStrategyinCrossRegionHedgingAvailabilityStrategyto differentiate SDK default strategies from custom ones. Updated the constructor to accept this flag. [1] [2] [3]Dynamic PPAF Enablement:
GlobalEndpointManager.csto dynamically enable or disable PPAF based on theenablePartitionLevelFailoverflag retrieved from the database account properties. Added logic to reset the availability strategy to null if PPAF is disabled and no custom strategy is set. [1] [2]Default Hedging Thresholds:
DefaultHedgingThresholdInMillisecondsandDefaultHedgingThresholdStepInMillisecondsinDocumentClient.csfrom private to internal for broader accessibility within the SDK.InitializePartitionLevelFailoverWithDefaultHedgingto use the newSDKDefaultCrossRegionHedgingStrategy.Tests for PPAF Functionality:
ReadItemAsync_WithPPAFDynamicOverrideinCosmosItemIntegrationTests.csto validate dynamic PPAF enablement, hedging behavior, and fallback when PPAF is disabled. This includes fault injection and diagnostics validation.End to End Validation:
CreateItemAsync: Strong Consistency Account with Direct Mode:
CreateItemAsync: Strong Consistency Account with Gateway Mode:
CreateItemAsync: Session Consistency Account with Direct Mode:
CreateItemAsync: Session Consistency Account with Gateway Mode:
[Note: The Orange graph indicates the number of requests processed in the North CentralUS region, where as the Blue graph indicates the number of requests processed in the Central US region.]
Type of change
Please delete options that are not relevant.
Closing issues
To automatically close an issue: closes #5304