First OpenVMS Boot On IA64

vaxzilla writes "At 3:31pm EST on Friday, January 31st, 2003, OpenVMS for the Intel IA64 architecture successfully booted and ran a DIR command. The Intel Itanium family of processors is the third architecture supported by OpenVMS in its 25 year history. Originally it ran on Digital Equipment Corporation VAX systems; in the early 1990s, support was added for the DEC Alpha processors. Following the acquisition of DEC by Compaq, and more recently Compaq by HP, the Itanium and Itanium2 port of OpenVMS is now being undertaken by HP. Congratulations on a job well done to the folks at ZK03 in Nashua, NH!"

Comments

Yeah, yeah, yeah....

[spurious cowherd]

.....it's cool

Now, get off the stick & build the Alpha EV8+

Re:64 bit architecture: illusionary performance

[ctr2sprt]

Performance is not the reason to go to 64-bit. The reason is the 64-bit address space, which allows individual processes to access 2^64 bytes of memory as a contiguous region. The IA32 ("x86") has a kludge which lets a system have up to 64GB RAM, but each segment can still only reference 4GB at most. If your operating system happens to use a flat memory model, like Linux does, this limits each process to 4GB total.

4GB is still a lot by any standard, but the problem is that the kernel, for example, needs to have some of its structures appear in the process's address space. Shared libraries also need to be in each process's address space, even if it's in memory only once. Even better, you need to leave room for the heap to grow as well as for user-loaded entities (like dlopen()'ed shared objects). In practice, I understand the default restriction for Linux is somewhere in the neighborhood of 1.5GB per process, though you can increase that to 3GB with some libc tweaks. There are a few kernel patches to raise that limit further to 3.5GB, but that's the absolute ceiling (and you are sacrificing what may be important things, like SysV shared memory segments).

Even now, it's not uncommon to see gaming machines with 1GB RAM or more. Even small servers will often have 4GB RAM. In a few years, the number of "high-memory" systems is only going to increase as advances in technology continue to drive down the cost of RAM and drive up the requirements of software. This is especially the case as databases become more important and commonplace in the business world. Everyone uses them now, but we can expect to see them used more often, and in more diverse places, than in the past.

There is also a hope among many of us that Intel and AMD will use this opportunity to create good chips, not just cheap ones. They have the opportunity to fix a lot of the stupid design decisions Intel made 20 years ago and put together a modern, clean system. Unfortunately, it doesn't look like this is going to happen (I don't think anyone at AMD has had an original idea in their entire lives, and Itanium is being designed by committee), but this is the hope. In short, we may not see any immediate performance gains, but in the long term, the design of the chips would enable faster improvements than we're getting with IA32s right now.