Unix System Administration

Computer Hardware

ISA Jar Jar Binks, ISA Annoying

• Industry Standard Architecture• Original PC Bus• 8-bit ISA

– 8.3MHz bus speed– 7.0 Mbytes per second

• 16-bit ISA– 8.3MHz bus speed– 15.9 Mbytes per second

Microchannel? Narrow Urethra?

• “IBM proprietary” bus meant to extend the ISA bus

• Primarily used in PS/2 and RS/6000 computers

• 8, 16, 32-bit transfers• Introduced concept of “bus mastering”• Not widely implemented and was rivaled by

the EISA bus architecture

EISA, Wanna Buy a Vowel?

• Originated in 1988 & 1989 by the “Gang of Nine” - AST, Compaq, Epson, HP, NEC, Olivetti, Tandy, Wyse & Zenith

• Designed as alternative to microchannel

• EISA connectors are a superset of ISA, so both EISA and ISA card will work in the same slot

• Bus mastering, shared interrupts

• 32-bits, 8.3MHz, 31.8 Mbytes/sec

Take the SBUS Downtown• Developed by Sun for its new SPARCstation

systems in 1989• Existing ISA and EISA weren’t powerful enough• Today, Sun is moving to the PCI Bus• However, SBUS I/O throughput is often 30-50%

faster than PCI implementations• Over 3 million SBUS slots are in use today• SBUS is an IEEE standard

VLB - Very Large Band-aid?• VESA Local Bus

• Created to help solve the need for large video transfers created by emerging graphical applications (e.g. Windows)

• Separate faster bus to augment the ISA bus.

• VL bus put on processors faster memory bus, or “local” to the processor.

• VL slots accept both VL & ISA cards

• 32-bit, 33MHz, 127.2 Mbytes/sec

PCI - Backwards, I C P

• Successor to VLB, EISA, Microchannel and SBUS

• Tends to co-exist with ISA still today

• Supports, bus mastering, shared interrupts, plug-n-play

• PCI - 32-bits, 33MHz, 127.2 Mbytes/sec

• PCI 2.1-64-bits, 66MHz, 508.6 Mbytes/sec

• New 100MHz bus support too!

Plug ‘n Pray

• Plug-n-Play was designed to make it easier for to install PC cards

• Macs and Suns had a type of play-n-play from their inception

• Eliminated the need to set dip switches or jumpers on the expansion card

• ISA cards were retrofitted with a type of plug-n-play

Let’s Get Graphic!

• AGP - Accelerated Graphics Port

• 32-bits wide (same as PCI)

• Runs at full bus speed of 66MHz (PCI runs at 1/2 bus speed).

• Minimum of 254.3 Mbytes/sec

• 2X and 4X mode for faster data transfer

• 4X = 1,017MB/sec, but theoretical 100MHz bus limit is 763MB/sec.

That’s UPA, not UPE

• UPA - Ultra Port Architecture

• Peak rate of 1.3GBytes/sec

• Packet switching instead of a bus

• Unlimited number of buses per system

• Can tie together other, commodity buses such as PCI

• Example: Sun Ultra Enterprise 450 has 6 PCI buses managed by a UPA

1+1 Does Not Always Equal 2

• Calculating bandwidth• bit-width/8 * bus-speed *

1,000,000/1,048,576 = Mbytes/second• 32 bits / 8 * 33.3MHz * 1,000,000/1,048,576

= 127.2 Mbytes/second• “M” in MHz = 1,000,000 (10^6)• “M” in Mbytes = 1,048,576 (2^20)

I’ve Seemed to Have Lost Some Memories. Oh, There They Are.

What Was I Talking About? Oh Yeah, Memory.

• DRAM - centipede memory chips

• SIMM - – 30 pin, 72 pin– ECC, EDO, FPM

• DIMM– 168 pin– SDRAM, PC100

Can You Factor the Form

• AT, Baby-AT• ATX, mini-ATX• LPX, mini-LPX, NLX

You Are Elle’s

• Hardware Specs– http://www.techfest.com/hardware/

• Sun UPA Spec– http://www.sun.com/microelectronics/

whitepapers/wp95-023.html

Wake Up!

• What does PCI stand for?

• What cards other than graphics cards fit in the AGP slot?

• Why would Sun switch to PCI bus if SBUS can attain 30-50% better I/O throughput?