| title | Troubleshooting issues and performance with SqlPackage |
|---|---|
| description | Learn how to troubleshoot with SqlPackage.exe. |
| ms.prod | sql |
| ms.prod_service | sql-tools |
| ms.technology | tools-other |
| ms.topic | conceptual |
| ms.assetid | 198198e2-7cf4-4a21-bda4-51b36cb4284b |
| author | dzsquared |
| ms.author | drskwier |
| ms.reviewer | maghan |
| ms.date | 7/29/2022 |
In some scenarios, SqlPackage operations take longer than expected or fail to complete. This article describes some frequently suggested tactics to troubleshoot or improve performance of these operations. While reading the specific documentation page for each action to understand the available parameters and properties is recommended, this article serves as a starting point in investigating SqlPackage operations.
As general guideline, better performance can be obtained via the .NET Core version of SqlPackage.exe.
- Download the zip for SqlPackage on .NET Core for your operating system (Windows, macOS, or Linux).
- Unzip archive as directed on the download page.
- Open a command prompt and change directory (
cd) to the SqlPackage folder.
It is important to use the latest available version of SqlPackage as performance improvements and bug fixes are released regularly.
If you have attempted to use the Import/Export Service to import or export your database, you may be interested in using SqlPackage.exe to perform the same operation with more control on optional parameters and properties.
For Import, an example command is:
./SqlPackage /Action:Import /sf:<source-bacpac-file-path> /tsn:<full-target-server-name> /tdn:<a new or empty database> /tu:<target-server-username> /tp:<target-server-password> /df:<log-file>For Export, an example command is:
./SqlPackage /Action:Export /tf:<target-bacpac-file-path> /ssn:<full-source-server-name> /sdn:<source-database-name> /su:<source-server-username> /sp:<source-server-password> /df:<log-file>Alternative to username and password, Universal Authentication can be used to authenticate via Azure AD with MFA. Substitute the username and password parameters for /ua:true and /tid:"yourdomain.onmicrosoft.com".
For issues related to timeouts, the following properties can be used to tune the connection between SqlPackage.exe and the SQL instance:
/p:CommandTimeout=: Specifies the command timeout in seconds when a query is executed. Default: 60/p:DatabaseLockTimeout=: Specifies the database lock timeout in seconds. -1 can be used to wait indefinitely, default: 60/p:LongRunningCommandTimeout=: Specifies the long running command timeout in seconds. The default value, 0, is used to wait indefinitely.
For the export and extract commands, table data is passed to a temporary directory to buffer before being written to the bacpac/dacpac file. This storage requirement may be large and is relative to the full size of the data to be exported. Specify an alternative temporary directory with the property /p:TempDirectoryForTableData=<path>.
The schema model is compiled in memory, so for large database schemas the memory requirement on the client machine running SqlPackage.exe may be significant.
By default, SqlPackage sets the maximum server parallelism to 8. If you note low server resource consumption, increasing the value of the MaxParallelism parameter may improve performance.
Logs are essential to troubleshooting. Capture the diagnostic logs to a file with the /DiagnosticsFile:<filename> parameter.
Additional performance-related trace data can be logged by setting the environment variable DACFX_PERF_TRACE=true before running SqlPackage. To set this environment variable in PowerShell, use the following command:
Set-Item -Path Env:DACFX_PERF_TRACE -Value trueFor imports that contain large tables or tables with many indexes, the use of /p:RebuildIndexesOfflineForDataPhase=True or /p:DisableIndexesForDataPhase=False may improve performance. These properties modify the index rebuild operation to occur offline or not occur, respectively. Those and other properties are available to tune the SqlPackage.exe Import operation.
A common cause of performance degradation during export is unresolved object references, which causes SqlPackage to attempt to resolve the object multiple times. For example, a view is defined that references a table and the table no longer exists in the database. If unresolved references appear in the export log, consider correcting the schema of the database to improve the export performance.
In scenarios where the OS disk space is limited and runs out during the export, the use of /p:TempDirectoryForTableData allows the data for export to be buffered on an alternative disk. The space required for this action may be large and is relative to the full size of the database. That and other properties are available to tune the SqlPackage.exe Export operation.
During an export process the table data is compressed in the bacpac file. The use of /p:CompressionOption set to Fast, SuperFast, or NotCompressed may improve the export process speed while compressing the output bacpac file less.
As an alternative operation to obtain the database schema and data while skipping the schema validation, perform an Extract with /p:ExtractAllTableData=True and /p:VerifyExtraction=True.
The following tips are specific to running import or export against Azure SQL Database from an Azure virtual machine (VM):
- use Business Critical or Premium tier database for best performance
- use SSD storage on the VM and ensure there is enough room to unzip the bacpac
- execute SqlPackage from a VM in the same region as the database
- enable accelerated networking in the VM
For more information on utilizing a PowerShell script to collect more information about an import operation, please see a TechCommunity blog post on the topic.
- SqlPackage overview
- Learn more about SqlPackage Import
- Learn more about SqlPackage Export