IBM / Mainframe

Mainframes

History

• System between Hardware and Application

• first use of an Architecture on the IBM System 360

Usage

Technology Trends

Observations:

• Core Frequency stagnated -> #cores started increasing

• #Transistors growing

• Single Thread Performance (slowly) increasing

• Demand and energy consumption has drastically increased
  • AI made this much worse.
  • Dennard scaling has stopped recently, which lead to increased consumption

⇒ We cannot continue to build computers like before.

How is IBM different?

Fails & How to address

• Hard Fail
  • Bugs Pre- / post-Silicon Verification & Formal Verification
  • Manufacturing Issue Testing, Redundancy & Margins
  • Aging Margins

• Soft Fail
  • Random Event redundancy & better technology and design
  • Electrical Noise electircally robust design point

Mainframe VS Small Machines

• costs are reduced with large system (Example: Prime Video)

• many small systems need large & complex software

Specifications

Depending on configuration: up to

Example Workload: 25 billion encrypted transactions/day (Redundancy excluded!)

Easy to Use

• Many technologies are integrated in Hardware and firmware stack
  • developer doesn’t need to care about that.

Efficient

• Chips are good in scaling

• IBM Z can efficiently distribute workload onto multiple cores.
  • effective for peak load

• Support for Garbage Collection, AI, Encryption, and more

Redundancy

• redirection of resources
  • still works with partial hardware missing
  • with HW functionality, archives complete software runtime without interruption
  • The System can run uninterrupted by normal affairs.

• Everything exists twice
  • Unmatched reliability by using redundant elements and error correction, e.g. in L2-caches
  • Mainframe don’t have a single point of failure
  • Replace Hardware while still running

Secure and Reliable

• data encrypted automatically
  • Regulators are eager for secure and reliable systems.
  • You need to be able to prove to regulators that you provide these requirements.
  • e.g: prevent example Buffer Overflows (by blocking it on a lower level).

• Post-Quantum Secure

full backwards compatibility