91–100 of 134 posts
This feels like a baby step towards Arm being able to emulate z/Arch workloads, maybe with a bit of secret sauce for certain specific operations, which doesn't seem very much like IBM.
ARM can emulate z workloads. https://hercules-390.github.io/html/index.html (or QEMU, for partition level emulation).
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A single mainframe can handle workloads that would take dozens of x86 cloud servers, with nine nines of uptime. If you can afford it it pays for itself in terms of reliability and scalability.
That may be true but the dozens of x86 servers are cheaper and easier to use.
Not explained in the article: Every single physical core on the chip decodes and executes both s390x and Arm AArch64 instructions, dynamically switching between the two ISA modes and convert them into micro ops. Mode switching is hypervisor-driven. And those chips are fast. 5.7 Ghz 2nm node. For who: When you need to run Linux programs on high security, mission critical environment. Others should not care.
https://www.servethehome.com/ibm-z-and-linuxone-dual-isa-pro...
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More like mid-2000s, even with the least charitable interpretation. There was a time when IBM dominated console CPUs for a massively successful generation (PS3, Xbox 360, Nintendo Wii).
It's a little more complex than that, IMO. For starters, IBM did also do the CPU for the GameCube, and that was likely a part of the Wii using an upgraded PPC arch for that. On the flipside, there is the theory (I think even Copetti brings it up in their XBox 360 Architecture breakdown [0]) that IBM using the Cell PPE for the 360's tri-cores left a sour taste in Toshiba, but more-so Sony's mouths. I think the big 'X…
AMD worked on a ARM core https://en.wikipedia.org/wiki/AMD_K12 but I'm not sure it would had work, they were never the best on the power consumption, so I'm not sure it would have been a good choice for the Switch.
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Possible different micro ops for different semantics. They also don’t mix instructions sets within the same process - the diagram I saw had ARM Linux as a guest under z/VM or KVM. For generations now no OS (not VM, not z/OS) hasn’t seen the bare metal machine, only ran under the PR/SM hypervisor, which is what does the logical partitions now. In order to properly run OSs for the 360 and 370 generations, s390x also ha…
I found this article with the diagram that you mention: https://wccftech.com/ibm-worlds-first-dual-architecture-proc... The diagram is the last picture, and according to it you choose the ISA at the VM level: either Linux on s390x or Linux on arm64, but not both on the same VM.
why is IBM moving forward that way
Because ARM is the future.
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ARM has better software support for AI applications and half of their presentation was about their inference accelerators that can go in the mainframes (and POWER machines). IBM mainframes are almost designed by their users. The previous generation skipped a lot of speed boost on the CPU side because their users didn’t want the machine to blow over their power delivery limits. Now, with their architecture behind it,…
Does anyone else make an ARM CPU that is expressly designed for performance with good cooling ?
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Even though their CPUs are insanely fast, the real power of mainframes is in their IO. The amount of data you can push through those machines is absolutely mind blowing.
Historically this was because each I/O "channel" was a separate computer that handled the actual communication with the device, be it a terminal, disk, tape drive, card reader, printer, etc. and exchange data with the CPU via DMA. This allowed mainframe CPUs, which in the past weren't particularly fast, to handle huge workloads involving hundreds or thousands of users. These days, even commodity computers get blazing…
Mere mortals such as me, have to make do with cloud-based clusters where the IO is distributed across multiple machines connected by very fast interconnects, but they don't behave as a single machine, nor have the IO always accessible at local bus speeds.
> Mainframes phone home immediately if they detect problems and an IBM service person will be on site the same day to fix it.
The joke usually went like this: technician shows up to fix the machine, operator says "We didn't call you", to what the technician answers "You didn't. Your computer did"
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At this point no one is buying into mainframes are they? So they are just selling to the existing pool of users for which the price just has to come in under the cost/risk of rewriting all their ancient stuff.
They are mostly leased, I think.
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The z mainframe team does good technical work but then the high price cancels out all the value of that work. I'm not sure if that counts as innovation or not.
At this point no one is buying into mainframes are they? So they are just selling to the existing pool of users for which the price just has to come in under the cost/risk of rewriting all their ancient stuff.
If you want to be a high-volume consumer bank (insurance is similar - it's about processing a high volume of transactions), you have few alternatives. You can get a couple mainframes (you should place them in different datacenters), with their extreme reliability and stability, or you can build your infrastructure with commodity distributed systems, but then you'll need to build the same level of reliability out of your unreliable components. Current solutions are getting really good at that, but it's your job to integrate them. In the end, it's not really a matter of how much money you spend, but how you spend it - the numbers will closely match.
Regulators don't really care how you do it, as long as you don't fail to provide adequate guarantees to your customers (banking is extremely regulated, and customers are well protected).