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| 5/24 |
| 2006/10/24-26 [Computer/HW/CPU] UID:44947 Activity:moderate |
10/24 http://en.wikipedia.org/wiki/Symmetric_multiprocessing "With the exception of a few rare 80486 systems, the x86 SMP market began with the Intel Pentium processor supporting up to two processors ....." Wasn't soda an 8-CPU 386SX machine more than a decade ago? \_ I think at peak it had 20 processors, and yes, they were 386. -tom \_ Yes, that would be the Sequent era (1992-1997). Soda Mark 2 had 8 386s, Soda Mark 3 had 16 386s and Soda Mark 4 had 20 386s. http://www.csua.berkeley.edu/computing/hardware/soda-mark-ii.html http://www.csua.berkeley.edu/computing/hardware/soda-mark-iii.html http://www.csua.berkeley.edu/computing/hardware/soda-mark-iv.html "[W]e must mustn't forget the days when the dry and cracked skin that we just shed were vigorous and bright with new colors. The next chance you have, hold a glass high to the past and drink to Soda MkIV, the last of the great Sequents." \_ I'm obviously too young. 22 386s in one machine? In 1995? Huh? I guess it was really good a multi-tasking. \_ Remember that it was *free* in 1995. The machine was built the late 80s, when the 386 was top-of-the-line. \_ and yes, those sequent systems were awesome at multitasking. Unfortunately the slow-ass cpu's were very slow at single tasks. However, it was ideal for its use as a multi-user, multi-purpose system. \_ Did the fastest Pentium-something CPU in 1995 perform twenty times as fast as a 386DX 20MHz (in terms of mips, I guess)? I don't remember which Pentium was top-of-the-line back then. \_ iirc, 1995 the fastest Pentium was 133 MHz. This was about as fast as a 486 running at 266 MHz or a 386 running at 533 MHz (ie nearly 25x faster than a 386 running at 20MHz). \_ I google'd for "8088 SMP", and I found "The SNC is an Intel 8088 based SMP system ..." in a non-free article. Can 8088 really support SMP??? \_ Why not? SMP is an old old old concept in CS. \_ I was just puzzled because Intel advertised one of the recent Pentium-whatever chip as the first x86 chip to support SMP. |
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| en.wikipedia.org/wiki/Symmetric_multiprocessing Most common multiprocessor systems today use an SMP architecture. SMP systems allow any processor to work on any task no matter where the data for that task is located in memory; operating system support, SMP systems can easily move tasks between processors to balance the workload efficiently. On the downside, memory is much slower than the processors accessing them, and even single-processor machines tend to spend a considerable amount of time waiting for data to arrive from memory. SMP makes this worse, as only one processor can access memory at a time; NUMA which dedicates different memory banks to different processors. This allows processors to access memory in parallel, which can dramatically improve memory throughput if the data is localized to specific processes (and thus processors). On the downside, NUMA makes the cost of moving data from one processor to another more expensive, meaning that balancing a workload is more expensive. Beowulf), in which not all memory is available to all processors. The former is not widely used or supported (though the high-powered 3D chipsets in modern videocards could be considered a form of asymmetric multiprocessing), while the latter is used fairly extensively to build very large supercomputers. In this discussion a single processor is denoted as a uni processor(UN). uniprocessor systems, which comprise the largest percentage of the market. Due to the nature of the different programming methods, it would generally require a separate project to support both uniprocessor and SMP systems with maximum performance. Programs running on SMP systems do, however, experience a performance increase even when they have been written for uniprocessor systems. kernel handles them can run on an idle processor instead. The effect in most applications (eg games) is not so much a performance increase as the appearance that the program is running much more smoothly. Otherwise, the additional processors remain idle and the system functions as a uniprocessor system. In cases where many jobs are being processed in an SMP environment, administrators often experience a loss of hardware efficiency. Software programs have been developed to schedule jobs so that the processor utilization reaches its maximum potential. Good software packages can achieve this maximum potential by scheduling each CPU separately, as well as being able to integrate multiple SMP machines and clusters. PowerPC (specifically G4 and G5 series, as well as earlier PowerPC 604 and 604e series) processors. In all cases, these systems are available in uniprocessor versions as well. Opteron 800 series and the above-mentioned UltraSPARC, SPARC64, MIPS, Itanium, PA-RISC, Alpha and POWER processors. High-end systems, with sixteen or more processors, are also available with all of the above processors. Athlon MP processors could be used with up to two processors in a system, and Intel Pentium II Xeon and Intel Pentium III Xeon processors could be used with up to four processors in a system natively. |
| www.csua.berkeley.edu/computing/hardware/soda-mark-ii.html Sequent Model: Symettry S27 Processor: 8 Intel 386 Operating System: Dynix 3x (BSD 42 based) Memory: ? |
| www.csua.berkeley.edu/computing/hardware/soda-mark-iii.html Sequent Model: Symettry S81 Processor: 16 16 Mhz Intel 386 Operating System: Dynix 3x (BSD 42 based) Memory: 80 Mb Disk Space: ? |
| www.csua.berkeley.edu/computing/hardware/soda-mark-iv.html Donated by: Sequent Location: CSUA Machine Room, 340 Soda Hall Sent to Excess and Salvage in Fall 1998 I am mistily recalling an early Sunday morning after a harrowing fourteen hour drive... Picture the scene: A U-Haul with Oregon plates, its shocks creaking under the weight contained within, is backed up to the fourth floor entrance of Soda Hall. The few volunteers wait with a hush until the back door rolls open, then... Hardware of a bygone era spills forth, to be carted off to the CSUA office by waiting hands. Soon enough it's going instead to the machine room for the office overfloweth. Then suddenly the good cheer stops as the last of the mobile equipment rolls off the truck bed, and plainly all that the next few minutes hold is cut hands, torn ligaments, and slipped disks... Or with any luck, no slipped disks, since that would have made dragging them all down from Oregon pointless. Yes, there they sat, gleaming cubes of misery and despair: About 150 pounds each, though it felt more like a thousand. Each held the promise of another day without "clean up yer shit!" The sounds of toil and human exertion filled the morning air as the disks were hauled in and carefully, oh so carefully, placed in the racks, each man shaking for fear of being pinned beneath one of the unforgiving behemoths and knowing full well that if the falling disk did not kill him, surely he would lose a limb as the price of continued life. Though we are evolving to meet the needs of our future, we must mustn't forget the days when the dry and cracked skin that we just shed were vigorous and bright with new colors. The next chance you have, hold a glass high to the past and drink to Soda MkIV, the last of the great Sequents. |