Phantom: A High-Performance Key-Value Store
Phantom is a cutting-edge embedded key-value storage solution that offers exceptionally high write throughput while ensuring low-latency data access. Inspired by HaloDB, Phantom harnesses the power of log-structured data files and hash indexes to deliver reliable performance, albeit without support for range scans.

Key Features

• High Write Throughput: Optimized for environments with intensive write operations, making it an ideal choice for applications that require rapid data ingestion.
• Low Latency Access: Designed to provide quick data retrieval times, enhancing overall application responsiveness.
• Simple and Effective Architecture: Utilizing time-tested design principles, Phantom balances high performance with maintainability.

Getting Started

To set up Phantom, simply add the dependency to your Maven or Gradle project. Here’s how to include it in your build files:
Maven:

<dependency>  
    <groupId>io.github.tuannh982</groupId>  
    <artifactId>phantom</artifactId>  
</dependency>  

Gradle:

implementation 'io.github.tuannh982:phantom:+'  

Create a Database Instance

Setting up a new database instance is straightforward:

String path = "/path/to/your/db/dir";  
DB db = new PhantomDB(  
       new File(path),  
       PhantomDBOptions.builder()  
               .numberOfIndexingThread(2 * Runtime.getRuntime().availableProcessors())  
               .compactionThreshold(0.5f)  
               .dataFlushThreshold(8 * 1024 * 1024)  
               .maxKeySize(8)  
               .maxFileSize(32 * 1024 * 1024)  
               .maxTombstoneFileSize(8 * 1024 * 1024)  
               .offHeapHashTable(true)  
               .estimatedMaxKeyCount(16)  
               .memoryChunkSize(4 * 1024 * 1024)  
               .build()  
);  

Performing Basic Operations

Phantom supports a variety of operations for data manipulation. Here are a few examples:

• Get a Value:

byte[] key = new byte[] {...};  
GetResult result = db.get(key);  
byte[] read = result.getValue();  

• Put a Value:

byte[] key = new byte[] {...};  
byte[] value = new byte[] {...};  
ModifyResult result = db.put(key, value);  
boolean success = result.isSuccess();  

• Delete a Value:

byte[] key = new byte[] {...};  
ModifyResult result = db.delete(key);  
boolean success = result.isSuccess();  

Closing the Database Instance

Always remember to cleanly close the database instance when done:

db.close();  

Important Notes

Currently in development, this project does contain known bugs. It is recommended to utilize the master branch for the most recent updates and bug fixes rather than the pre-release version.

Future Enhancements

Planned improvements include unit testing, performance benchmarks, and support for distributed modes to advance the capabilities of Phantom even further.

With Phantom, you can ensure robust, efficient, and scalable key-value data management suitable for modern applications.