![[RSS]](http://tweakimg.net/g/if/v2/icons/rss_small.png){kind=icon}
Conclusion
After having run behind for years, Intel grabs the performance crown back with the introduction of the Xeon Woodcrest. AMD did not have a sufficient technical response to the new architecture and had to cut the prices of its Opterons in order to prevent it from losing its competitiveness. A calmer management guild might have been content with that, but the new aggressive Intel does not want to leave any doubt that the company is ahead again, and does not allow its competitor any breathing space. The step from two to four cores widens the gap between Xeon and Opteron considerably. Of course, it is not entirely fair to compare Intel's quad-core, which is based on a new architecture, to AMD's current K8 dual-core. But the fact of the matter is that this is precisely the choice for customers during the next six months. That period will see sales of x86 processors worth about 12 billion dollars, so there is a golden opportunity for Intel to grab market share back.
AMD has all of its hope set on Barcelona, the quad-core Opteron. According to the latest rumours, it will be introduced at a clock speed of 2.5GHz at the most - a little under the speed of Intel's 2.66GHz quad-core. As yet, it is unclear what effect the changes to the 'K8L' design will have on the performance, but if we take the easy assumption that it will do the same amount of work per clock tick, it will be at a small disadvantage as far as raw computing power is concerned. However, this is likely to be compensated by the L3 cache with integrated memory controller. Intel will have an answer to this in the form of higher clock speeds, possibly still at 65nm, or else with the coming 45nm production technology. Rumour has it that Intel's 45nm quad-cores will exceed 3.0GHz, which is something AMD will have a hard time following.
Barcelona has a further significant advantage against Clovertown: it scales to 4 and 8 sockets. The Xeon MP 'Tulsa' can barely stand up to the current Opteron, but is helpless against the new generation of quad-cores. That is why Intel is putting a lot of work into Tigerton, a Clovertown version that is capable of being used in heavier systems. The biggest problem is not the processor – which is virtually identical – but the chip sets. With four separate 1066MHz buses and a 64MB cache in the northbridge, Intel's own Clarksboro chip set will smoothen the communication between the sockets considerably compared to today's standards. Meanwhile, IBM is working on X4 – the successor of the X3 'Hurricane' – which can scale to 32 sockets by simulating the Opteron's Numa architecture in the chip set. How these will do compared to the Barcelona is anyone's guess.
In our benchmark, Clovertown did not offer tremendous gains, and especially MySQL was - initially - disappointing. The latest development version partially solves the problems: performance with eight cores is no longer dramatically bad, but on average, heavy loading does not make things better than a double dual-core using the old version of the software. But we did register a 19% higher peak, although possibly Woodcrest will also profit from the changes to version 5.0.32-bk, so the gains cannot be solely attributed to the extra cores. PostgreSQL does better, but average gains of 19% is not really something to write home about, given that it is the result of doubling the number of cores in the machine.
Possibly, developments on the hardware side are going to fast for the open source community. But Intel's architecture may also be responsible: with limited bus band width and no shared cache, AMD does not recognize Clovertown as a quad-core proper. We may also have to point the finger at ourselves and accept that this type of server is not intended for the Tweakers.net database. But we shall find out if this holds as soon as we get our hands on a heavier Opteron machine.
Acknowledgements
Tweakers.net would like to thank Melrow for lending us a Clovertown-server, Peter Zaitsev from the MySQL Performance Blog for checking our configuration, ACM and moto-moi for setting up and executing the benchmarks, and Mick de Neeve for the English translation of this review.
Earlier articles in this series
13-11-2006: Intel Xeon 'Woodcrest' 3,0GHz (Apollo 5)
4-9-2006: Intel Xeon 'Woodcrest' 2,66GHz
30-7-2006: AMD Opteron Socket F 2,4GHz
27-7-2006: Sun UltraSparc T1 vs. AMD Opteron
19-4-2006: Xeon vs. Opteron, single- and dualcore (in Dutch)
AMD has all of its hope set on Barcelona, the quad-core Opteron. According to the latest rumours, it will be introduced at a clock speed of 2.5GHz at the most - a little under the speed of Intel's 2.66GHz quad-core. As yet, it is unclear what effect the changes to the 'K8L' design will have on the performance, but if we take the easy assumption that it will do the same amount of work per clock tick, it will be at a small disadvantage as far as raw computing power is concerned. However, this is likely to be compensated by the L3 cache with integrated memory controller. Intel will have an answer to this in the form of higher clock speeds, possibly still at 65nm, or else with the coming 45nm production technology. Rumour has it that Intel's 45nm quad-cores will exceed 3.0GHz, which is something AMD will have a hard time following.
Barcelona has a further significant advantage against Clovertown: it scales to 4 and 8 sockets. The Xeon MP 'Tulsa' can barely stand up to the current Opteron, but is helpless against the new generation of quad-cores. That is why Intel is putting a lot of work into Tigerton, a Clovertown version that is capable of being used in heavier systems. The biggest problem is not the processor – which is virtually identical – but the chip sets. With four separate 1066MHz buses and a 64MB cache in the northbridge, Intel's own Clarksboro chip set will smoothen the communication between the sockets considerably compared to today's standards. Meanwhile, IBM is working on X4 – the successor of the X3 'Hurricane' – which can scale to 32 sockets by simulating the Opteron's Numa architecture in the chip set. How these will do compared to the Barcelona is anyone's guess.
In our benchmark, Clovertown did not offer tremendous gains, and especially MySQL was - initially - disappointing. The latest development version partially solves the problems: performance with eight cores is no longer dramatically bad, but on average, heavy loading does not make things better than a double dual-core using the old version of the software. But we did register a 19% higher peak, although possibly Woodcrest will also profit from the changes to version 5.0.32-bk, so the gains cannot be solely attributed to the extra cores. PostgreSQL does better, but average gains of 19% is not really something to write home about, given that it is the result of doubling the number of cores in the machine.
Possibly, developments on the hardware side are going to fast for the open source community. But Intel's architecture may also be responsible: with limited bus band width and no shared cache, AMD does not recognize Clovertown as a quad-core proper. We may also have to point the finger at ourselves and accept that this type of server is not intended for the Tweakers.net database. But we shall find out if this holds as soon as we get our hands on a heavier Opteron machine.
AcknowledgementsTweakers.net would like to thank Melrow for lending us a Clovertown-server, Peter Zaitsev from the MySQL Performance Blog for checking our configuration, ACM and moto-moi for setting up and executing the benchmarks, and Mick de Neeve for the English translation of this review. Earlier articles in this series 13-11-2006: Intel Xeon 'Woodcrest' 3,0GHz (Apollo 5) 4-9-2006: Intel Xeon 'Woodcrest' 2,66GHz 30-7-2006: AMD Opteron Socket F 2,4GHz 27-7-2006: Sun UltraSparc T1 vs. AMD Opteron 19-4-2006: Xeon vs. Opteron, single- and dualcore (in Dutch)
