Computer Hardware
Focus Items Design systems that meet business needs Hardware industry trends Problems Legacy hardware (and software) Dealing with growth Improving fault tolerance
Terms (CPU) (1) Central Processing Unit (CPU) Many machines have multiple CPUs Servers scale from processors Many CPUs are designed to support virtualization Processor speed Measured in GHz. A measure of the internal clock
Terms (CPU) (Illustration)
Terms (CPU) (2) Most machines have multiple cores A “core” is a separate work engine within the cpu
Terms (Cache) (Memory) CACHE – Memory directly connected to the CPU Fast Memory (Primary storage) Volatile storage to store data Not all memory is the same Some provides error correction Performance differences Density
Terms (Bus) Bus Communicates from CPU to memory, disk, network controllers, etc. Bus speed is an important consideration
Terms (Disk) Disk (Secondary storage) Hard ATA, SATA, SCSI, Optical CD / DVD / Blu Ray Backup tape devices
Categories of Computers (lightweight devices) “Lightweight devices” Network computers Special purpose transaction terminals UPS / FedEx Browser-only devices (kiosks) Phones Tablets
Categories of Computers (Desktop) Market is shrinking because of tablet / phone horsepower These are the engineering workstations of yesterday
Categories of Computers (Servers) Oracle Sun / HP / IBM / Dell provide the lion’s share of todays servers Characterized by Multiple CPUs with multiple cores
Large Server (Example) SPARK Enterprise M processors / 4 cores per processor 4TB memory Storage measure in the pedabytes (NAS) IBM Power 795 Up to 256 processor cores book “book” and up to 8 books 16 TB memory All for about $1 million
Larger Server (Illustration)
Categories of Computers (Blade) A computer within a computer We buy a “blade chassis” containing Power supplies / cooling / external media We buy blade computers that go into the chassis Blades: Reduce power consumption and maintenance costs
Blade (Illustration)
Categories of Computers (Mainframe) These are really just the IBM Z series and a few special purpose devices
Categories of Computers (Distributed Computing) (Distributed computing) It’s really the software and not the hardware We just cluster multiple computers together Special purpose back ends TeraData database servers Storage Tek disk and tape sub systems Storage Area Networks (SAN)
Secondary Storage (Disk) Trends They are cheap commodity items < $ per terabyte Rated in mean time between failure (MTBF) 100,000 to 1.5M hours is common Multiple disks are connected to form disk subsystems
RAID Redundant disk arrays supply fault tolerance There are different types of RAID Level 1 uses separate disks (mirroring) Level 2 uses striping There are others Example HP 3PAR StoreServ storage Fault tolerant Up to 2.2 PB of storage
Secondary Storage (Magnetic Tape) It’s still used for large archive sites Phone records, credit card records, and other historical data Tapes are enclosed in tape robotic sub systems We can store up to PB HP StoreEver ESL G3 Up to 12,006 tape cartridges
Secondary Storage (SAN) We are really just making data available to many clients Evolution Network Access Storage (NAS) put storage on the network instead of a server Storage Area Network (SAN) puts storage on it’s on it’s own ‘very fast’ network 2GB/Sec interconnect using Fibre channel
Printer Technology Desktop laser printers offer low TCO High speed production printers These compete against traditional offset presses Continuous roll input Up to 2500 pages per minute
Printer Technology (2) Kodak example system: About 75ft long and 15ft tall Will print both sides at 2 up(2 different documents side by side) Ink jet printer - 12 print heads -- 8 nine inch heads and 4 four inch heads. Running at 1000ft per minute Ink feeds from 275gal tanks
Printer Technology (3)
Printer Technology (4)
Balance in Systems The issue in configuring large systems is balance Choosing the right system for the job Disk (IO) is often the bottleneck Bus Speed Memory shortfalls Network bandwith
Scalability in Systems Systems must be able to grow with a business Expansion of an existing system by adding memory, disk or other components Expansion by adding additional servers to a cluster or server farm
Server Farms Many servers interconnected together
Server Farms (Load Balancing) Load balancing servers Dispatch request to the actual servers Monitor the health of the servers Monitor the load on the various servers
Titan Oak Ridge National Labs houses the “fastest” computer in the world
Titan 27,000 trillion calculations / second (27 petaflops) 299,008 CPU cores 18,688 AMD Opteron 18,688 K20x GPUs 710TB of memory Cost of 97 million
Fault Tolerance in Systems One server in a farm can fail leaving the others running Fault tolerant servers have multiple CPUs Failed memory will not cause a system to fail RAID allows disk failures without causing system failures
Economic Decisions Single vendor solutions vs. multivendor solutions Lease VS. buy decisions
Terms (Speed) Microsecond - 1/1000 second Millisecond – 1/1,000,000 second Nanosecond – 1/1,000,000,000 second Picosecond – 1/1,000,000,000,000 second Teraflop – Trillion (1,000,000,000,000) floating point operations per second
Terms (Storage) 1,000 bytes – Kilobyte 1,000,000 bytes – Megabyte 1,000,000,000 bytes – Gigabyte 1,000,000,000,000 bytes – Terabtye 1,000,000,000,000,000 bytes = Petabyte