Microcontrollers/ASICs v. General Purpose Microprocessors -- WAS: Opteron Vs. Athlon X2

[Bryan J. Smith]

"Bryan J. Smith" <b.j.smith at ieee.org> wrote:
> I'm sorry, but the 3-issue ALU of the Opteron can_not_ do
> 7.5 billion LOAD (the slowest part), FETCH-DECODE-XOR (the
> most simplistic part) and STOR operations per second!
>   ...
> BTW, with regards to the 333MHz, no offense, but you're
> ... there is a _huge_ difference between a CPU and a
> microcontroller with ASICs designed specifically for
> something.

Why use a layer-3 switch?

I mean, a layer-2 switch with a router on one port would be
cheaper?

Why put in a HBA for FC-AL or iSCSI?  I mean, with a fast
enough system, GbE is only about 100MBps, so why can't a
system handle it?

After all, TCP segmentation is only like addresses of windows
into packets of a larger blocks -- much like sectors are to
the windows of partitions on a storage array?

Especially when these powerful, costly layer-3 switches only
have a 200, 300 ... maybe 400MHz MIPS or ARM/XScale at their
cores?

So why would anyone consider an Intel IXP for networking
equipment anymore than they would an Intel IOP for their
storage equipment?  I mean, why wouldn't Intel just sell 1
type of XScale, why do they make different versions for
communications/networking (IXP) and system/storage (IOP)?

The system can handle it, they don't need anything, ASICs and
dedicated peripherals and their specialized instructions are
useless.

Heck, why aren't I using my server as a layer-3/4 router?! 
Throw in some 4-port GbE cards and I can do it better and
cheaper than a layer-3 switch!  So why not?

-- Bryan

P.S.  There is a reason why 3Ware calls the Escalade
7000/8000 a "Storage Switch" -- it's design is what you can
expect in a layer-3 router.  A microcontroller core with ASIC
peripherals and SRAM cache (just like network ASICs around a
microcontroller core) designed for one thing, queue, move and
replicate data.  Now I would _not_ use a 7000/8000 series
with only 1-4MB of SRAM for RAID-5 anymore than I would/could
use a layer-3 Ethernet switch that only has 1-4MB of SRAM for
NAT/PAT and network filtering duties.  But there are more
advanced cards, just like their are more advanced networking
equipment -- all often powered by little more than one
RISC/microcontroller core of a few hundred MHz.


-- 
Bryan J. Smith                | Sent from Yahoo Mail
mailto:b.j.smith at ieee.org     |  (please excuse any
http://thebs413.blogspot.com/ |   missing headers)