How to fix Error 2815 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: Error 2815 – Infinite Recompile Detected in Natively Compiled Module

Why This Error Happens

This error occurs when SQL Server’s query optimizer detects that a natively compiled stored procedure or module is triggering a recompilation loop, typically caused by schema changes, statistics updates, or parameter sniffing issues that invalidate the compiled execution plan repeatedly. In-memory OLTP natively compiled modules are particularly sensitive to this because they are compiled into native DLLs at creation time, and certain metadata changes force SQL Server to attempt recompilation on every execution rather than caching a stable plan. This condition often surfaces after a database schema migration, an in-place upgrade to SQL Server 2025, or when memory-optimized table statistics become stale or corrupted.

Step-by-Step Resolution Guide

Step 1: Identify the Affected Module and Database

  • Run the following query to resolve the database ID and module ID from the error message:
SELECT DB_NAME(2815_DB_ID) AS DatabaseName, OBJECT_NAME(2815_MODULE_ID, 2815_DB_ID) AS ModuleName;
  • Check the SQL Server Error Log (C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Log\ERRORLOG) for the exact timestamp and correlate with any recent schema or statistics changes.
  • Use Extended Events (xEvents) with the query_memory_grant_blocking and sp_statement_completed targets to trace the recompile loop in real time.

Step 2: Drop and Recreate the Natively Compiled Module

  • Script out the existing module definition using SSMS (right-click module > Script Stored Procedure as > CREATE To).
  • Drop the module manually:
DROP PROCEDURE dbo.YourNativeModuleName;
  • Recreate it with the NATIVE_COMPILATION option, ensuring the SCHEMABINDING clause is intact and parameter data types match the underlying memory-optimized table exactly.
  • Recompile it explicitly after creation using sys.sp_recompile is not supported for native modules, so instead force a fresh native DLL build via ALTER PROCEDURE ... WITH NATIVE_COMPILATION, SCHEMABINDING.

Step 3: Update Statistics on Memory-Optimized Tables

  • Natively compiled modules are highly sensitive to outdated statistics on the underlying memory-optimized tables.
  • Run the following for each referenced table:
UPDATE STATISTICS dbo.YourMemoryOptimizedTable WITH FULLSCAN;
  • Enable AUTO_UPDATE_STATISTICS_ASYNC at the database level to reduce future recompilation pressure:
ALTER DATABASE YourDatabase SET AUTO_UPDATE_STATISTICS_ASYNC ON;

Step 4: Apply the Latest Cumulative Update

  • Confirm your SQL Server 2025 build number via SELECT @@VERSION; and compare against the latest Cumulative Update (CU) on the Microsoft Update Catalog.
  • Known in-memory OLTP compiler bugs related to infinite recompile loops are frequently patched in CUs, so applying the latest build on Windows Server 2025 is critical.
  • Restart the SQL Server service (services.msc > SQL Server (MSSQLSERVER) > Restart) after patching.

Alternative or Verification Steps

  • Verify the fix by monitoring sys.dm_exec_query_stats for the module’s plan_generation_num column; a stable, non-incrementing value confirms the recompile loop is resolved.
  • If the issue persists, as a temporary workaround, convert the natively compiled module to an interpreted T-SQL procedure referencing the memory-optimized table, which bypasses the native compilation recompile logic entirely.