On 6/26/05, Duncan <[EMAIL PROTECTED]> wrote: > Tres Melton posted <[EMAIL PROTECTED]>, excerpted > below, on Sat, 25 Jun 2005 12:26:38 -0600: > > > Yea, that was my understanding too but that's not right with portage <= > > 2.0.51.19. Since I had never read otherwise I was in the habit of > > invoking emerge thusly; "emerge -avDut --newuse pkg-name" and I was > > getting screwed by the --update. > > Yes. I guess you posted your update mentioning that while I was in the > middle of composing my 300-line reply. <g> It all makes sense, now. > > > From the LKML it would seem that the kexec function's first real (and > > safe) use is to handle a kernel oops. The production kernel loads and > > reserves a space for and loads a small data gathering kernel. In the > > event of an oops the production kernel is in a questionable state so I/O > > is immediately disabled (lest ye smoke thy data) and control is > > transfered to the mini-kernel which can snapshot the running kernel, > > memory, and swap and safely write that data out to storage. Then the > > mini-kernel can cold boot the system resetting all the hardware and > > everything to a known good state. Most of the kernel devs are against > > any other use of kexec since I/O with a questionable current can put > > your job and sanity at risk and bypassing the hardware reset brings in > > all the issues of sw-susp leaving hardware in unknown (or not completely > > known) states. > > Yeah, I'd read about that in LWN's kernel coverage. That's why I > mentioned it. Nothing really new to me there, but I had been really brief > on that point (uncharacteristically so <g>), and expanding it for anyone > else following along is always helpful. Besides, reading the same thing > put slightly differently is always good, as it reinforces the concepts and > drives them home. > > >> One reboot alternative is to switch init levels, down to init 1 to stop > >> nearly everything, then back to init 3 (or whatever) to restart most of > >> the system. Note that on Gentoo, unlike on many distributions and *ix > >> versions, init 1 does NOT mean single user mode that shuts down all the > >> virtual terminals and what may be running from them. Thus, it's possible > >> to keep a long-running process alive either in another virtual terminal > >> (or in the background in your current terminal), or add them to a > >> couple custom init levels, one with your usual other system stuff in it as > >> well, one without most of it, then switch between those levels, so the > >> long-running process doesn't stop. > > > > If I'm going to go that far down then I'm going to reboot. For me, once > > I leave X there is no reason NOT to reboot. I know servers are totally > > different beast though. > > Well, I too spend most of my time in X (KDE), but am quite comfortable in > CLI as well, certainly to the point where I could never say once I leave X > there's no reason NOT to reboot. Sometimes, I'll switch to a CLI VT and > do my system maintenance tasks there, leaving X running in VT7. Other > times, I'll shut down X/KDE and do my maintenance stuff, then start it up > again. > > When I get the memory upgrade I'm looking at, not rebooting from an X > shutdown will likely become even MORE common. I'll /hate/ rebooting, > because with 4, possibly 8 gig of memory (I'm tempted to go to the full > 16, but it's too hard to zero out the CC again when the balance gets that > high), and apps normally only taking a quarter to a half a gig (it looks > like I'll occasionally run a full gig of app memory) most stuff will stay > in that 3-7 gigs of cache once read from disk the first time, so virtually > everything will be loaded from cache, not disk. Rebooting will of course > mean losing that cache, having to start over reading everything from slow > disk once again. That'll SUCK, likely enough that I'll be trying to avoid > it, even more than I do now, when it's no big deal. I'm not an uptime > freak, usually rebooting every few days (uptime of almost 5 days, now, > that one was a shutdown to depower the breaker box so I could trade out > the a/c breaker, as it was getting weak and tripping, not a good thing > here in Phoenix, with temps running ~45 C, 113 F, last week, a much more > reasonable 40 C this week, still 30 C, 86 F, @ 4 AM), but I can imagine > getting to the point where I'll complain about rebooting, since I rebooted > "only" a week or two ago. That'll be particularly likely with the new > SMP-suspend that's probably going to be in 2.6.13. Definitely looking > forward to that!
Just curious, what do you do with that much RAM? -- [email protected] mailing list
