Westmere-EP vs Sandy Bridge-EP Performance Preview

Over the next few months, Intel will be releasing several server and workstation class processors based on Sandy Bridge. Entry level workstation offerings include E3-1200 v2 and E5-1600, both reliable alternatives to regular desktop offerings. Dual socket processors include the E5-2400 series and the higher performing E5-2600. Finally, we have the quad socket E5-4600 series.

	E3-1200	E3-1600	E5-2400	E5-2600	E5-4600
Processor core	Ivy Bridge	Sandy Bridge-EP	Sandy Bridge-EN	Sandy Bridge-EP	Sandy Bridge-EP 4S
Socket	H2 (Socket 1155)	Socket 2011	B2 (Socket 1356)	Socket 2011	Socket 2011
Multiprocessing	1	1	2	2	4
Due date	Q2 2012	Q1 2012	Q2 2012	Q1 2012	Q2 2012

We have now seen some initial performance comparisons between Sandy Bridge-EP and Westmere-EP. A document leaked by a Chinese website (PDF file) revealed what sort of performance increase we can expect in Sandy Bridge-EP over Westmere-EP. Various benchmarks were run using an X5690 (with 6 cores/12 threads at 3.46 GHz base clock, 3.6GHz Turbo Clock) and an E5-2690 (8 cores/16 threads at 2.9 GHz), in a dual-socket setup with comparable configuration, except that the X5690 had 40 GB of DDR3-1333 in triple channel configuration and the E5-2680 had 32GB DDR3-1600 in quad channel configuration.

Giving the X5690 a baseline score of 1 in each test, we see some interesting results. Both chips have a similar TDP. The X5690 has a core speed 24% higher than E5-2690, but the latter has 33% more cores. Using the synthetic Linpack benchmark to measure matrix multiplication, E5-2690 scored a respectable 2.2. Using OLTP Database (TPC-C Oracle), E5-2690 scores 1.5, while using a middle tier java test (SPECjbb 2005) the score is 1.56. Integer throughput using SPECint_base2006 gives a score of 1.69. Moving to some technical computing tasks, Floating Point Throughput (SPECfp*_rate_base2006) gave a score of 1.82 and Memory Bandwidth (STREAM_MP Triad) scored 1.88. The average performance over these 6 applications is approx 1.78, indicating a projected performance increase of approximately 80% when moving from the high-end Westmere-EP offering to the equivalent Sandy Bridge-EP processor.

Comparing the Xeon 5600, E5-2400 and E5-2600 we can see the benefits of the newer systems, and why the E5-2600 series is so powerful.

	Xeon 5600 (Westmere-EP)	Xeon E5-2400 (Sandy Bridge-EN)	Xeon E5-2600 (Sandy Bridge-EP)
Cores	Up to 6	Up to 8	Up to 8
Threads	Up to 12	Up to 16	Up to 16
L3 cache	12 MB	Up to 20 MB	Up to 20 MB
Max memory channels per socket	3	3	4
Max memory speed	1333 MHz	1600 MHz	1600 MHz
Virtualization technology	Real mode support and transition latency reduction	Adds large VT pages	Adds large VT pages
New instructions	AES-NI	Adds AVX	Adds AVX
QPI frequency	6.4 GT/s	8.0 GT/s	8.0 GT/s
Inter-Socket QPI links	1	1	2
PCI Express	36 lanes PCIe 2.0 on chipset	24 Lanes/Socket Integrated PCIe 3.0	40 Lanes/Socket Integrated PCIe 3.0
Server/Workstation TDP	Server/Workstation: 130W/95W/80W/LV (Low Power)	Server: 95W/80W/LV	150W (Workstation Only)/135W/130W/115W/95W/80W/LV