Closes issue #38902

README.adoc

@@ -162,6 +162,99 @@ Generally, you will not need to use `spring-boot-loader` directly but work with
 The spring-boot-devtools module provides additional development-time features, such as automatic restarts, for a smoother application development experience.
 Developer tools are automatically disabled when running a fully packaged application.
 
+### ${\color{red} \space Virtual \space Threads \space Limitations \space and \space Best \space Practices \space in \space Spring \space Boot}$
+
+### Warning: Potential Risks of Incorrect Virtual Thread Usage
+
+Virtual threads in Spring Boot offer concurrent execution benefits but come with specific risks and limitations when used incorrectly:
+
+1. **External Resource Overload:** Excessive concurrent virtual threads might strain external resources like database connections or file I/O operations. This can lead to contention, depletion, or performance degradation when the number of threads surpasses the capacity of these resources.
+
+2. **Thread Starvation:** Uncontrolled creation of virtual threads can cause thread starvation, impacting system stability due to increased context switching and resource contention, ultimately affecting performance.
+
+3. **Blocking Operations Impact:** Operations that block for extended periods, like synchronous blocking I/O or long-running tasks, might nullify the benefits of virtual threads by causing delays and potentially blocking other threads.
+
+### Examples of Anti-Patterns and Potential Issues
+
+Certain Spring modules might exacerbate these problems:
+- **Spring JDBC or JPA:** Uncontrolled virtual threads might overload database connections, leading to bottlenecks or connection pool exhaustion.
+- **Spring Web:** Concurrently handling requests using virtual threads might overload I/O-bound operations, affecting response times or causing bottlenecks.
+
+### Quarkus Insight on Virtual Threads
+
+Quarkus, a related framework, highlights the limitations and risks of virtual threads in concurrent environments, cautioning against unchecked usage due to potential resource constraints and scalability issues.
+
+### Lack of Fine-Tuning in Spring Boot for Virtual Threads
+
+Spring Boot lacks extensive fine-tuning options for virtual threads, necessitating careful consideration and strategic usage.
+
+### Proposed Annotations for Virtual Threads
+
+Consider introducing annotations like:
+- **@RunOnVirtualThread:** Marks methods for execution on virtual threads.
+- **@VirtualThreadSafe:** Ensures thread safety in virtual thread environments.
+- **@NotVirtualThreadSafe:** Marks components or methods not suitable for virtual threads.
+
+### Emphasizing Careful Usage and Thorough Testing
+
+Before adopting virtual threads extensively, thoroughly test applications under various loads and scenarios to identify bottlenecks and resource constraints. Monitor thread usage and resource consumption regularly.
+
+### Cautionary Approach
+
+Excessive advertising of virtual threads might overlook the associated risks. Emphasize a cautious approach, encouraging users to consider the limitations and employ them judiciously.
+
+### Adding Custom MimeMappings
+**Step 1: Identify the MimeMappings File**
+
+Locate the configuration file responsible for MimeMappings. Typically, it's named web.xml or similar.
+
+**Step 2: Edit the MimeMappings**
+
+Open the identified configuration file.
+
+Look for the <mime-mapping> section or similar entries.
+
+To add a new MimeMapping, use the following xml format:
+<mime-mapping>
+    <extension>[FILE_EXTENSION]</extension>
+    <mime-type>[MIME_TYPE]</mime-type>
+</mime-mapping>
+
+Replace [FILE_EXTENSION] with the file extension (e.g., pdf, docx) and [MIME_TYPE] with the corresponding MIME type (e.g., application/pdf, application/vnd.openxmlformats-officedocument.wordprocessingml.document).
+
+Save the changes to the configuration file.
+
+**Step 3: Restart the Application (if required)**
+
+If the changes to the configuration file require a server/application restart, perform the necessary steps to restart the application.
+
+### Configuring MimeMappings Using Properties
+**Step 1: Identify Properties File**
+
+Locate the properties file used for configuring your application.
+
+
+**Step 2: Add MimeMappings Properties**
+Open the properties file.
+
+**Add or modify properties related to MimeMappings using the following css format:**
+
+mimeMappings.[FILE_EXTENSION]=[MIME_TYPE]
+Replace [FILE_EXTENSION] with the file extension (e.g., pdf, docx) and [MIME_TYPE] with the corresponding MIME type (e.g., application/pdf, application/vnd.openxmlformats-officedocument.wordprocessingml.document).
+
+**For example (bash):**
+
+`mimeMappings.pdf=application/pdf
+mimeMappings.docx=application/vnd.openxmlformats-officedocument.wordprocessingml.document
+Save the changes to the properties file.`
+
+**Step 3: Load Properties in Application**
+
+Ensure that the application loads and utilizes these properties during runtime. This may involve a configuration setup within your application codebase to read and apply these properties for MimeMappings.
+
+**Step 4: Restart the Application (if required)**
+
+If changes to the properties file necessitate a server/application restart, proceed to restart the application accordingly.
 
 
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