AMD EPYC 8324P / 8324PN Siena 32-Core Siena Linux Server Performance

Last month AMD launched the EPYC 8004 "Siena" 4th Gen EPYC processors to round out their Zen 4 server processors with the expansive Genoa, Genoa-X, Bergamo, and Siena product portfolios. The new EPYC 8004 series are designed to maximize the power efficiency for server deployments from the data center to edge, teclo, and other non-traditional server environments. Up for testing today is an initial look at the Siena performance in the form of the EPYC 8324P and EPYC 8324PN 32-core parts for seeing how they stack up against 32-core Intel Xeon Scalable "Sapphire Rapids" performance.

As a reminder about the EPYC 8004 series line-up, the Siena processors range from 8 to 64 core SKUs, Siena is designed to be only a single socket platform, and Zen 4C cores are employed for greater energy efficiency and maximizing CPU density. There is also only six memory channels with Siena compared to 12 channels with Bergamo / Genoa(X) as well as a reduction in the number of PCIe / CXL lanes.

The 32 core parts this generation are the EPYC 8324P and 8324PN, with the latter being their "PN" variant that is for Network Equipment Building System (NEBS) compliant deployments that can withstand a greater operating temperature range of -5 to 85 C compared to 0 to 75 C for the P parts. The EPYC 8324P has a 2.65GHz base frequency and 3.0GHz boost compared to the EPYC 8324PN having a 3.0GHz boost too but a 2.05GHz base frequency. The EPYC 8324P has a 180 Watt TDP while the EPYC 8324PN has a 130 Watt TDP. The EPYC 8324P has a configurable TDP from 155 to 225 Watts while the Siena PN parts do not have a configurable TDP.

Siena, Milan, and Genoa. Socket SP6 for Siena looks very similar to Socket SP3 with Milan and prior EPYC processors while being much smaller than the new Socket SP5 introduced by Genoa.

The 1KU pricing on the EPYC 8324P is $1895 USD while the 8324PN pricing is $2125 USD. The pricing is quite competitive with the Intel Xeon Gold 6421N 32-core processor having a list price of $2368 USD although the cheapest in-stock price I was able to find was $2520 and at some retailers sells north of $3,000. The Xeon Gold 6421N is the main comparison point for today's benchmarking with this 32-core Sapphire Rapids processor having a 185 Watt TDP, 1.8GHz base frequency, and 3.6GHz turbo frequency.

The AMD EPYC 8324P/8324PN testing occurred with AMD's Cinnabar reference server for Siena. Testing occurred with 8 x 32GB DDR5-4800 memory and four 3.2TB Micron 7450 Max NVMe SSDs in RAID10 with EXT4 as the storage during the benchmarking. The Intel Xeon Gold 6421N was similarly configured in a single socket ASRockRack SPC741D8-2L2T/BCM server with four Micron 7450 Max NVMe SSDs. The Xeon testing took place both with six memory channels to match the Siena capabilities and then at eight memory channels for the full potential of the processor.

All of the benchmarking occurred with Ubuntu 23.10 to represent a leading-edge Linux environment with the Linux 6.5 kernel and GCC 13.2 compiler for having a fresh software stack for all of this EPYC and Xeon servr benchmarking. In total the following processor configurations were tested for this review:

EPYC 8324P: The AMD EPYC 8324P in its default configuration / power state (performance determinism) / default 180 Watt TDP.

EPYC 8324P - Power: The EPYC 8324P in its default configuration aside from switching over to the power determinism mode.

EPYC 8324P - 155W: The AMD EPYC 8324P when dropped to the lowest configurable TDP value of 155 Watts.

EPYC 8324PN: The NEBS 32-core model, the EPYC 8324P in its default configuration of 130 Watts.

EPYC 8324PN - Power: Running the EPYC 8324PN in the power determinism mode.

Xeon Gold 6421N: The Intel Xeon Gold 6421N Sapphire Rapids 32-core processor in its default configuration and all eight memory channels populated.

Xeon Gold 6421N - 6c RAM: Running the Intel Xeon Gold 6421N with just six of the eight memory channels populated to match the memory channels used by AMD EPYC Siena.

From there I fired off dozens of benchmarks for this initial look at AMD EPYC Siena performance under Linux. During testing there was performance-per-Watt and CPU power consumption monitored via the RAPL/PowerCap interfaces.

Performance-per-dollar metrics were also calculated based on current Intel and AMD CPU pricing. Additionally, given that we're comparing number of memory configurations, the DIMMs were included as part of the cost. A $150 per DIMM basis was used for the going rate on the used 32GB Samsung M321R4GA0BB0-CQKMG DDR5 memory modules in both the 6 channel and 8 channel configurations on each server.