Re:No SMP? Huh?
by
life4m
·
· Score: 3, Interesting
No, SMP was only absent in OpenBSD. It was just not a priority for the project. Nevertheless, it is a welcome addition.
Can anyone "in the know" shed some light about the qualities of the OpenBSD code? How does OpenBSD's SMP model compare to fine-grained locking, such as in FreeBSD-CURRENT?
When I see how much effort and trouble has gone and is going into locking down the FreeBSD kernel, I am guessing that OpenBSD's SMP support will be fairly primitive to start with. Or are there heavy ports from FreeBSD?
The initiative to ADD SMP to OpenBSD (and the announcement that "a full time developer was working on it")
occurred less than 4 months ago. It took FreeBSD years to get SMP "right", during an adolesence where stability seriously suffered.
Neither NetBSD nor OpenBSD have a significant fraction of the user base of FreeBSD (and an infinitessimal share compared to Linux), and neither NetBSD nor OpenBSD have comparably-sized development teams. FreeBSD SMP had antecedants to build on as well. So logic dictates that it should take longer for OpenBSD SMP to be "ready".
OpenBSD went through a comparable architecture change when they swapped virtual memory systems a few years ago, and several subsequent major releases of OpenBSD had serious VM stability problems (many of them synchronization issues). SMP is even harder (and more of it involves synchronization).
So, is there some mitigating factor here that would convince anyone who was paying attention to deploy a mission-critical system on SMP OpenBSD in 2004?
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No, SMP was only absent in OpenBSD. It was just not a priority for the project. Nevertheless, it is a welcome addition.
Can anyone "in the know" shed some light about the qualities of the OpenBSD code? How does OpenBSD's SMP model compare to fine-grained locking, such as in FreeBSD-CURRENT?
When I see how much effort and trouble has gone and is going into locking down the FreeBSD kernel, I am guessing that OpenBSD's SMP support will be fairly primitive to start with. Or are there heavy ports from FreeBSD?
The initiative to ADD SMP to OpenBSD (and the announcement that "a full time developer was working on it") occurred less than 4 months ago. It took FreeBSD years to get SMP "right", during an adolesence where stability seriously suffered.
Neither NetBSD nor OpenBSD have a significant fraction of the user base of FreeBSD (and an infinitessimal share compared to Linux), and neither NetBSD nor OpenBSD have comparably-sized development teams. FreeBSD SMP had antecedants to build on as well. So logic dictates that it should take longer for OpenBSD SMP to be "ready".
OpenBSD went through a comparable architecture change when they swapped virtual memory systems a few years ago, and several subsequent major releases of OpenBSD had serious VM stability problems (many of them synchronization issues). SMP is even harder (and more of it involves synchronization).
So, is there some mitigating factor here that would convince anyone who was paying attention to deploy a mission-critical system on SMP OpenBSD in 2004?