OCP CDU (Deschutes) Standard Overview
The provided visual summarizes the key performance metrics of the CDU (Cooling Distribution Unit) that adheres to the OCP (Open Compute Project) ‘Project Deschutes’ specification. This CDU is designed for high-performance computing environments, particularly for massive-scale liquid cooling of AI/ML workloads.
Key Performance Indicators
- System Availability: The primary target for system availability is 99.999%. This represents an extremely high level of reliability, with less than 5 minutes and 15 seconds of downtime per year.
- Thermal Load Capacity: The CDU is designed to handle a thermal load of up to 2,000 kW, which is among the highest thermal capacities in the industry.
- Power Usage: The CDU itself consumes 74 kW of power.
- IT Flow Rate: It supplies coolant to the servers at a rate of 500 GPM (approximately 1,900 LPM).
- Operating Pressure: The overall system operating pressure is within a range of 0-130 psig (approximately 0-900 kPa).
- IT Differential Pressure: The pressure difference required on the server side is 80-90 psi (approximately 550-620 kPa).
- Approach Temperature: The approach temperature, a key indicator of heat exchange efficiency, is targeted at ≤3∘C. A lower value is better, as it signifies more efficient heat removal.
Why Cooling is Crucial for GPU Performance
Cooling has a direct and significant impact on GPU performance and stability. Because GPUs are highly sensitive to heat, if they are not maintained within an optimal temperature range, they will automatically reduce their performance through a process called thermal throttling to prevent damage.
The ‘Project Deschutes’ CDU is engineered to prevent this by handling a massive thermal load of 2,000 kW with a powerful 500 GPM flow rate and a low approach temperature of ≤3∘C. This robust cooling capability ensures that GPUs can operate at their maximum potential without being limited by heat, which is essential for maximizing performance in demanding AI workloads.
with Gemini
Lechuck Park 