IBM Z mainframe
Hacker ApprovedRanked 2 of 6 servers by recommenders
Recommended for reliability, availability and fast I/O, and for running old workloads on modern hardware. Main caveat: high price and binding to IBM hardware.
Recommended for reliability, availability and fast I/O, and for running old workloads on modern hardware. Main caveat: high price and binding to IBM hardware.
31 people gave an opinion
- recommend it
- 23
- criticize it
- 8
- approval share
- 74%
Recommended in 11 of 13 months
- November 2025: recommended
- December 2025: recommended
- January 2026: recommended
- February 2026: recommended
- March 2026: not recommended
- April 2026: recommended
- May 2026: not recommended
- June 2026: recommended
- July 2026: recommended
- August 2026: recommended
- September 2026: recommended
- October 2026: recommended
- November 2026: recommended (month in progress)
Why it carries the badge
- 23 people recommend itNeeds 10 or more, met.
- 2.9 recommenders for every criticNeeds 2 to 1 or better, met.
- Recommended in 11 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Reliable, fault tolerant, highly available
“The modern mainframe is the best state of the art platform for computing, in both reliability and efficiency.”
Comment from 23 Feb 2026 in “IBM Plunges After Anthropic's Latest Update Takes on COBOL” “If you can afford it it pays for itself in terms of reliability and scalability.”
Comment from 27 Aug 2026 in “IBM Unveils Next Generation Dual-Architecture Processor for IBM Z and LinuxONE” “reliability, availability, and service features mainframes have/had”
Comment from 29 Nov 2025 in “WinApps: Run Windows apps as if they were a part of the native Linux OS” - Comment from 2 Apr 2026 in “IBM Announces Strategic Collaboration with Arm”
Custom, state-of-the-art silicon hardware
“To their credit, IBM is still making zArchitecture chips that aren’t completely humiliated by x86 and ARM.”
Comment from 24 Nov 2025 in “Are consumers just tech debt to Microsoft?” “Their hardware is still cool custom built silicon and imo state of the art”
Comment from 2 Apr 2026 in “IBM Announces Strategic Collaboration with Arm” “IBM makes some really amazing hardware at the very top of the market”
Comment from 28 Apr 2026 in “The Quiet Resurgence of RF Engineering” Very fast I/O and processing
“they have access to the same caching mechanisms as the main processor (which are quite insane)”
Comment from 2 Apr 2026 in “IBM Announces Strategic Collaboration with Arm” “From what I have heard they are still really fast with I/O”
Comment from 3 Jun 2026 in “CT scans of BYD car parts” “feels like a normal server that's just ludicrously fast”
Comment from 26 Aug 2026 in “IBM Unveils Next Generation Dual-Architecture Processor for IBM Z and LinuxONE” Runs legacy workloads well
“They stick with COBOL because it runs well on the mainframe.”
Comment from 23 Feb 2026 in “IBM Plunges After Anthropic's Latest Update Takes on COBOL” “they get to run the old workloads on modern hardware”
Comment from 21 Sep 2026 in “What Sun got wrong”
What people warn about
Each mark is one comment
High price and cost
“IBM stuff is likely to expensive and optimized for different things”
Comment from 5 Aug 2026 in “Oxide Computer raises $445M (SEC Form D)” “the high price cancels out all the value of that work”
Comment from 26 Aug 2026 in “IBM Unveils Next Generation Dual-Architecture Processor for IBM Z and LinuxONE” “so goddamn weird and expensive”
Comment from 31 Jan 2026 in “An anecdote about backward compatibility” Binds customers to IBM hardware
“IBM has done this, despite it being an inferior technical solution, because it binds those who choose it to IBM hardware.”
Comment from 1 Oct 2026 in “Adding Floating-Point Decimals for Fun and Profit” “the way IBM writes support contracts incentivizes customers to work very hard at moving workloads to Windows/UNIX”
Comment from 27 Jan 2026 in “Windows 11's Patch Tuesday nightmare gets worse” “Mainframes are the opposite, you usually get the full monty machine that is extremely limited by licensing.”
Comment from 25 May 2026 in “IBM Spins Off the First Pure-Play Quantum Chip Foundry” Restrictive licensing and contracts
“Mainframes are the opposite, you usually get the full monty machine that is extremely limited by licensing.”
Comment from 25 May 2026 in “IBM Spins Off the First Pure-Play Quantum Chip Foundry” “utterly appalled they'd treat their big customers like that”
Comment from 21 Sep 2026 in “What Sun got wrong” “you can't use any of them without paying”
Comment from 18 Jun 2026 in “AMD silently removes memory encryption from consumer Ryzen CPUs”
Other servers people recommend
The four most recommended other servers, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| Oxide Computer rack | 92 | 20 | 82% | 10 | — | Approved |
| IBM Z mainframeThis page | 23 | 8 | 74% | 11 | — | Approved |
| IBM POWER | 13 | 5 | 72% | 10 | — | Approved |
| Nvidia GH200 server | 12 | 2 | 86% | 2 | — | — |
| IBM AS/400 | 11 | 6 | 65% | 8 | — | — |
What people said
All 35 comments that mention it, newest first. Each links to the original comment.
“their mainframes are just unique machines, I'm very fond of them”
“If you absolutely need to scale something vertically, IBM Z is the final stop on the line.”
“IBM systems don't have APIs. Everything is configured, manually, through archaic mainframe terminals.”
“IBM has done this, despite it being an inferior technical solution, because it binds those who choose it to IBM hardware.”
“you need nearly a data center's worth of hardware to provide the volume and availability of one mainframe, and that can fit in one cabinet”
“utterly appalled they'd treat their big customers like that”
“they get to run the old workloads on modern hardware”
“IBM always invests a lot of money in hardware to keep the mainframe perceptually leading edge”
“IBM's mainframes are pretty unique”
“the dozens of x86 servers are cheaper and easier to use”
“If you can afford it it pays for itself in terms of reliability and scalability.”
“feels like a normal server that's just ludicrously fast”
“the high price cancels out all the value of that work”
“the IBM Z series is still a huge player there”
“IBM mainframes still run the world”
“IBM stuff is likely to expensive and optimized for different things”
“IBM mainframes give the right answers.”
“Outside of the mainframe, power business, some research”
“you can't use any of them without paying”
“From what I have heard they are still really fast with I/O”
“Mainframes are the opposite, you usually get the full monty machine that is extremely limited by licensing.”
“IBM makes some really amazing hardware at the very top of the market”
“very reliable, fault tolerant system”
“they have access to the same caching mechanisms as the main processor (which are quite insane)”
“Their hardware is still cool custom built silicon and imo state of the art”
“IBM mainframes are wonderfully isolated from physical hardware”
“The modern mainframe is the best state of the art platform for computing, in both reliability and efficiency.”
“They stick with COBOL because it runs well on the mainframe.”
“IBM is great stuff, but it's all workhorses.”
“so goddamn weird and expensive”
“the way IBM writes support contracts incentivizes customers to work very hard at moving workloads to Windows/UNIX”
“IBM still dominates the large, billion-dollars worth mainframe market”
“The awe induced when standing in front of a brand new, kitted out x95 frame with all its drawers full”
“reliability, availability, and service features mainframes have/had”
“To their credit, IBM is still making zArchitecture chips that aren’t completely humiliated by x86 and ARM.”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.