## The file size of Web App is too big (over 900 MB)
To enhance performance, scalability and management, you should store all content on DXP Web Apps using BLOB storage (and/or SQL database). The Web App's local file system is meant for _code only_, and therefore normally does not have large amounts of disk space.
To improve stability and performance further, the underlying Web App is using local cache, which also has a limited size; see [Azure App Service Local Cache overview (Microsoft)](🔗). This limit is currently set to _900 MB_.
The deployment engine for DXP verifies that the Web App is below this limit. If the limit is exceeded, it may affect the ability to swap a new slot into production, and the time it takes to warm up a new instance during scale outs, and the reliability of backups, to name a few examples.
## The implementation of an ipSecurity section in web.config
This is not supported because it will not work reliably in DXP. See [Restrict environment access](🔗) for information about implementng IP restrictions in a supported way.
## Metadata file could not be found for DXP Service
During DXP deployment to preproduction or production environments, the following error message may appear when the application starts:
_error CS0006: Metadata file 'D:\\local\\Temporary ASP.NET Files\\root\\X\\X.dll' could not be found._
The dll is most often _App\_Code.dll_ or _App\_global.asax.dll_ but it may be any top-level file.
Top-level files include the _global.asax_ file and all files in the bin and _App\_Code_ folders.
If this error occurs, set the **optimizeCompilations** attribute of the compilation element in _web.config_ to **false**.
For DXP Service, **optimizeCompilations** does not improve anything; you cannot update individual files without restarting an app service because the App Service Local Cache feature is enabled. Also, the deployment flow always deploys to an empty wwwroot in the slot that is in a stopped state, and after files are deployed, it starts up and warms up; that starts the compilation (for preproduction and production environments). See also: [Understand ASP.NET Dynamic Compilation](🔗).