// Test buffer allocation
    RdmaMemoryRegion region = manager.getSendRegion(1024);
    assertNotNull(region);
    assertTrue(region.getSize() >= 1024);
    
    // Test buffer release
    manager.releaseSendRegion(region);
    
    // Test reuse
    RdmaMemoryRegion region2 = manager.getSendRegion(1024);
    assertNotNull(region2);
    
    manager.cleanup();
}
```

        try (RdmaBufferManager bufferManager = new RdmaBufferManager(provider)) {
            // Test basic buffer allocation
            RdmaMemoryRegion sendRegion = bufferManager.getSendRegion(4096);
            assertNotNull(sendRegion, "Send region should not be null");
            assertTrue(sendRegion.getSize() >= 4096, "Send region should be at least 4KB");