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No More Need To Reboot Fedora w/ Ksplice
An anonymous reader writes "Ksplice, the technology that allows Linux kernel updates without a reboot, is now free for users of the Fedora distribution. Using Ksplice is like 'replacing your car's engine while speeding down the highway,' and it can potentially save your Linux systems from a lot of downtime. Since Fedora users often live on the bleeding edge of Linux development, Ksplice makes it even easier to do so, and without reboots!"
But do the windows "snap" to one side of the screen? See? Simple! ($100 please)
http://www.imagepoop.com/image/660/I-Reboot-As-Much-As-I-Get-Laid.html
There's no -1 for "I don't get it."
"Using Ksplice is like 'replacing your car's engine while speeding down the highway,'"
So in other words it's something you'd never want to risk doing because it'd almost certainly cause a crash?
I think they should've thought about a different analogy for this one...
Lisp systems did this 30+ years ago: reload new compiled functions, and keep going. New calls go to the new function, old function becomes garbage when no more threads are executing it.
When you have around 1500 production servers to patch, such as with the memmap 0 bug last year, doing them one-by-one, or even in small batches, remotely over IP KVM takes a long-ass time. This is nice for those types of situations.
Windows user is middle of the road. He has brains and money but not enough of either.
And frankly, I'd still feel a little more comfortable with a reboot, since I'd worry a bit about state consistency of kernel and client processes.
This in theory can be a problem, but each kernel update has to be prepared individually, so someone (once again, this is the theory) has looked at the kernel modifications and made sure it won't cause problems. This isn't an automatic thing that can work with any kernel (don't try to use it to go from a 2.4 kernel to a 2.6 kernel), and if there are major changes, say a new scheduler or something, then someone needs to write code that will move the data from the old scheduler to the new scheduler.
Mainly its used for security updates which are probably a line of code changed, or a function changed, and there is no difficulty with inconsistencies (unless maybe someone is in the middle of trying to exploit the buffer overflow, but they avoid that problem by making sure no threads are in the functions that are being patched). This is my understanding of how it works.
Qxe4
Other than just screwing around in your garage it's still $50 a year per server if you actually need.
Processes in the 'D' state cannot be killed, even by root. They're waiting on I/O and nothing short of giving them the I/O they're waiting for or rebooting will kill them.
No, the grandparent means uninterruptible sleep.
Processes sleep in a way that can't be interrupted in some cases. For instance, when writing to a file. The logic of that that if it was possible, the application would have to retry the interrupted call, and since a write is assumed to be uninterruptible nobody tries to check if it was interrupted.
This ocassionally creates problems, like when something in the disk subsystem goes wonky, and a write call never returns, leaving the process sleeping and unkillable forever.
There was a patch to create a killable state, that allows fatal signals to be processed in such cases, since the process would die immediately anyway. I'm not sure how fully is this integrated, but while I remember unkillable processes in the past, I don't think I had any in the last couple of years.
Seriously? I patched 5500 linux servers in 24 hours *by myself*, all the while they were churning through collider data from the LHC. This would be, in my opinion, what I would call a production environment. Shortcuts are nice, but sometimes you don't need them if your environment is engineered properly.
Seriously? I patched 5500 linux servers in 24 hours *by myself*, all the while they were churning through collider data from the LHC. This would be, in my opinion, what I would call a production environment. Shortcuts are nice, but sometimes you don't need them if your environment is engineered properly.
That's slightly different. I assume you're at a CMS or ATLAS T2 center and frankly most of those systems were worker nodes that could be taken down for a minute or too for a reboot as jobs were drained off of them and they went idle. A quick reboot and they'll show up in condor or pbs a minute or two later and start processing jobs. The gatekeepers and gateways for the SE would be more complicated but if you got them up within a minute or two, most if not all of the running jobs wouldn't notice.
"When you sit with a nice girl for two hours, it seems like two minutes. When you sit on a hot stove for two minutes, it
Your post is accurate =) *shakes fist*
well for starters, Apple doesn't officially support using Blades or Virtual Machines (they did "allow" VMWare to do it", but only on Mac Hardware) which are where many enterprise Linux installs are living nowdays on IBM, Dell, or HP farms. Apple hardware doesn't really have an enterprise presence or connections to the type of SAN hardware running in many places. You have to ASK to buy a Mac and not many IT departments would allow that. You don't have to ASK to try out a Linux install, you can beg "forgiveness" later on because generally you won't cost the company monie$$, or at least risks they wouldn't have spent money on in the first place. While Macs are cool, as far as enterprise uses, it is still pretty limited. I have several macs (so I'm not a hater) but I could never get my IT manager to take them seriously.