I'd argue that IBM's contributions in that timeframe were more about about validating it from a large business perspective than about technical contributions (that tended to focus on large system performance which wasn't actually that important for Linux taking off).
Linux's multiprocessor support was ...lackluster at best... prior to IBM contributing all the Sequent (Dynix) derived multiprocessing stuff. Hyperthreading/Multicore started to get "normal" even in consumer systems only a couple years later, so that injection was pretty critical.
Likewise, a lot of Linux's development inertia and cultural acceptance came from being a cheap and consistent alternative to screwing around with the profusion of expensive and mutually incompatible proprietary Unixes in the Server and (as clusters co-evolved) HPC market.
On the broader issue, the tension here is that IBM thinks the value proposition of RHEL is "Supported" and (I suspect) almost everyone else regards the value proposition of RHEL as "standard base." I think it's more likely that the "standard base" for srs bsns Linux in the markets where RHEL is the standard would rebase than IBM having any success trying to squeeze customers, and if that happens the value of "Owning RHEL" suddenly shrinks dramatically. Honestly, all it would take is the RHEL-likes like Alma and Rocky to agree on a coordination mechanism that isn't matching RHEL - could be through a major public interest like CERN, could be through an existing commercial interest like coordinating with Oracle (ew), could be via one of the several entities that does commercial support for RHEL-likes ... there are options.
Oracle being a gigantic litigious parasite on society is a broader issue, and I understand regarding commercial RHEL-likes as more of a problem, but even they have been funding a lot of backport-to-LTS type work.
>Linux's multiprocessor support was ...lackluster at best... prior to IBM contributing all the Sequent (Dynix) derived multiprocessing stuff. Hyperthreading/Multicore started to get "normal" even in consumer systems only a couple years later, so that injection was pretty critical.
It was certainly needed over time but capabilities from things like RCU out of Sequent weren't that important in the 2000 timeframe. And a lot of IBM's contributions didn't come online until the v4 kernel.
None of this is to minimize IBM's contributions to Linux over time but I'd argue pretty strongly that IBM's endorsement of Linux for enterprises in January 2000 is what really moved the needle in the short run.
Here's what one of the people most directly involved told me a few years ago:
"By the late 90s, it was clear that Linux was becoming more and more important. And we formed a major task force to see to what extent IBM should embrace Linux and this happened in 1999. And the task force came back and said, we absolutely should embrace Linux, that it was going to be an incredibly important part of computing, that we should embrace Linux across all of IBM's offerings. And that IBM should become a major supporter of Linux.
"And I still remember very well in December of ‘99, I called Sam Palmisano, the head of IBM Systems Group. And I said, Sam, the task force recommends that we should embrace Linux. And Sam said, okay, Irving, we will do that. But you have to now come over and run an IBM Linux initiative. And I said to Sam, okay, we were pretty much done with our internet strategy. So I was no longer needed to run the Internet division And I said to Sam, when do you want to announce it? And Sam said, how about now? And I said Sam. It's the Christmas holidays. Maybe we should wait until the new year. And in the second week of January of 2000, we made a major announcement saying that IBM would embrace Linux across all of these offerings. And in fact, later that month in January of 2000, I gave a keynote at LinuxWorld, which was taking place in the Javits Center in New York City, about IBM’s Linux initiative.
I was mixing up where the big multiprocessor changes that went into the 2.5 series in that 2000-2005 era came from.
I was thinking of the the basic kernel preemption stuff and sched_setaffinity syscall + userspace plumbing like taskset that is _extremely_ consequential on little multicore/SMT machines, but the prominent name on a lot of that was Robert Love and he was at MontaVista at the time.
The Dynix parts that arrived via IBM were, as you say, mostly NUMA and RCU stuff based on Paul McKenney's work, which also went in in the same major overhaul during the 2.5 series but weren't quite so immediately consequential to smaller systems.
I hadn't heard that anecdote, but that is a neat tale of IBM using their gravitas at the time to legitimize Linux.
SGI also did a lot of scalability work in that time frame, as part of their migration from MIPS+Irix to Itanium+Linux. In the end they got Linux working on IIRC up to 4096 processors.
Yes, certifying DB2 for Linux (back in 1998, https://slashdot.org/index2.pl?fhfilter=db2+linux, scroll to bottom) was an absolutely earth-shattering event that announced that Linux had arrived. I think that event (and of course Oracle and Sybase a few months prior) really sounded the death knell for big-iron UNIX.
But in 1999, IBM ported Linux to run on System 390 (https://slashdot.org/index2.pl?fhfilter=mainframe+linux) and I remember there was a story that some IBM scientist booted more than 30,000 Linux instances on a mainframe on his lunch break. This research led to the big SUSE partnership, as well as open-sourcing other enterprise-y software like JFS and putting a big devteam to make the kernel ready for real SMP (Linux didn't have efficient+mature SMP even into the early aughts, although a few companies had built some massive SMP boxes.)
>Linux didn't have efficient+mature SMP even into the early aughts, although a few companies had built some massive SMP boxes
Including IBM. (Forget when they did their big stackable X-series server.) A lot of the tech eventually became applicable to even super-mainstream dual-socket servers but I wonder how much money was largely wasted on building and trying to sell larger scale-up boxes.
But, yeah, IBM was one of the big investors in OSDL (and their own Linux Technology Center) which had a lot of scale-up focus which made a lot of the legal claims of another 3-letter company pretty much misaligned with the timeline.
HN loves to hate Oracle, IBM, SAP, Adobe and friends, without getting the point that many startups that go through HN programs never achieve half of what they produce.
What do startups have to do with IBMs business direction and processes? How does this relate to my point? Not every startup being successful somehow means that I shouldn't comment on IBMs recent business decisions?
We seem to even be hating on RedHat now. (I was bummed about the Centos thing too). People on this thread are acting like Redhat doesn't even release any free software.
Well, they used to. Now there's software to be had in exchange for money. Mostly written by people outside of IBM. And the source access they used to provide is disappearing one move at a time. Which leaves a void and an opportunity, but also a lot of annoyance at IBM.
Except roll the clock back a bit and your would have been talking about Lotus, Machine Learning, and Unix/PowerPC.
And we see what IBM has done with leadership in those areas, as well as a long line of other areas where they somehow managed to turn themselves into a 3rd rate competitor despite being in the right place at the right time.
So, you have to ask yourself, for example how its possible that people are falling over themselves to build a RISCv ecosystem from the ground up, when openpower has been around for a decade now, and IBMs been looking for partners there since the original AIM alliance.
Looking at their yearly revenue, doing quite alright.
The RISCv ecosystem is a pipe dream that people will finally get it when they start dealing with major boards relying on extensions, or board designs that aren't as open as the CPU itself.
There have yet to evolve practical applications for current quantum computers.
No one cares about Java anymore, beyond legacy support. They bought RedHat with their massive reserve of capital from more successful times.
IBM is still in business because they can build on massive reserves from the time where they literally created the market for commercial computing. That was indeed influential. Now they slowly burn those reserves and have a crackhead sales team that knows how to sell mainframes and subsequently suck those customers dry.
The new generation of graduates has no idea what IBM does, let alone what a mainframe is. New talent for maintaining Cobol codebases is so rare to come by, that they pay the Linux foundation to offer free courses on Cobol.
IBM's success is a relict of the past. It will die when the last guy that knows how to maintain Cobol dies. Good riddance.
Also note that IBM contributions to Linux kernel in 2000, was one of the reasons it actually took off.