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Advice needed;Sleep? or Shutdown?

Message #1 - Posted 2005/05/19 - jeffrey lohn

i was lucky enough to find a really nice 1.25 dual MAC FW800 on CRAIGSLIST. :)

would appreciate advice on whether i should shut the computer down at night...
or just let it go to "Sleep" with the "Sleep after 20 minutes of inactivity" choice in the Energy saver control panel? which means if i use the computer every day, i would never shut it down?

Message #2 - Posted 2005/05/19 - Gregory Weston

Previously, jeffrey lohn wrote:

i was lucky enough to find a really nice 1.25 dual MAC FW800 on CRAIGSLIST. :)

would appreciate advice on whether i should shut the computer down at night...
or just let it go to "Sleep" with the "Sleep after 20 minutes of inactivity" choice in the Energy saver control panel? which means if i use the computer every day, i would never shut it down?

We never shut ours down unless we know we're going to be away for a while and even then it's mostly to prevent any chance of damage to the machine due to powerline anomalies.

And when I say we never shut down, I'm not just whistling Dixie. I hot-plugged RAM in my G5 the other day. Yes I'm serious and no it wasn't on purpose. And no, the memory wasn't recognized until I restarted. That would've been pretty cool, though.

G

Goal 2005: Convincing James Hetfield to cover the Strawberry Shortcake "Are You Berry Berry Happy?" song.

Message #3 - Posted 2005/05/19 - Erik

Previously, Gregory Weston wrote:

Previously, jeffrey lohn wrote:

i was lucky enough to find a really nice 1.25 dual MAC FW800 on CRAIGSLIST. :)

would appreciate advice on whether i should shut the computer down at night...
or just let it go to "Sleep" with the "Sleep after 20 minutes of inactivity" choice in the Energy saver control panel? which means if i use the computer every day, i would never shut it down?

I've heard it's a good idea to shut down now and then, as the machine does some behind the scenes cleaning up and the like in the boot process. I've also heard this is a load of malarky, so who knows... none the less, I've shut down once a week (every Wednesday night to be precise) since the 7 days, and have never had any problems. Energy Saver covers my tail after a half hour when/if I have to dash off in a hurry.

We never shut ours down unless we know we're going to be away for a while and even then it's mostly to prevent any chance of damage to the machine due to powerline anomalies.

When I'm going away for a while, I shut down for the same reasons, but also unplug from both the power and phone lines. Only takes a minute... I consider it cheap insurance against lightning spikes and whatnot.

And when I say we never shut down, I'm not just whistling Dixie. I hot-plugged RAM in my G5 the other day. Yes I'm serious and no it wasn't on purpose. And no, the memory wasn't recognized until I restarted. That would've been pretty cool, though.

...wow!

Erik

Message #4 - Posted 2005/05/19 - Gregory Weston

Previously, Erik wrote:

Previously, Gregory Weston wrote:

Previously, jeffrey lohn wrote:

or just let it go to "Sleep" with the "Sleep after 20 minutes of inactivity" choice in the Energy saver control panel? which means if i use the computer every day, i would never shut it down?

I've heard it's a good idea to shut down now and then, as the machine does some behind the scenes cleaning up and the like in the boot process.

It does a little bit. It also does quite a bit during the small hours of the morning when left on and awake. At least a few people have released tools to reschedule that maintenance or do it on demand.

We never shut ours down unless we know we're going to be away for a while and even then it's mostly to prevent any chance of damage to the machine due to powerline anomalies.

When I'm going away for a while, I shut down for the same reasons, but also unplug from both the power and phone lines. Only takes a minute... I consider it cheap insurance against lightning spikes and whatnot.

Yeah. And good that you mention the phone line. The only actual electrical damage I've ever suffered was the loss of a modem that I didn't think to disconnect from the line. It was really weird, because I think that was the first time I ever though to myself "I should unplug the equipment; I've got a bad feeling about this storm."

And when I say we never shut down, I'm not just whistling Dixie. I hot-plugged RAM in my G5 the other day. Yes I'm serious and no it wasn't on purpose. And no, the memory wasn't recognized until I restarted. That would've been pretty cool, though.

...wow!

Completely freaked me out when I realized what I had done. Whipped out the hardware test CD real fast. No problems detected and the system's been running fine for almost a week now. My theory is that the machine is engineered such that DIMM slots that are found to be empty at startup aren't actually hot.

Goal 2005: Convincing James Hetfield to cover the Strawberry Shortcake "Are You Berry Berry Happy?" song.

Message #5 - Posted 2005/05/20 - roj

I've heard it's a good idea to shut down now and then, as the machine

does some behind the scenes cleaning up and the like in the boot process.

In OS 9, RAM gets fragmented after you open and close a lot of applications and eventually there aren't any holes left to open any applications. So shutting down once a day takes care of that. This is not malarky. I have a memory mapper application that actually shows how my memory gets fragmented.

So, you OS X weenies, does OS X defrag RAM in the background so that it's not a problem in OS X?

Message #6 - Posted 2005/05/20 - roj

I've heard it's a good idea to shut down now and then, as the machine

does some behind the scenes cleaning up and the like in the boot process.

In OS 9, RAM gets fragmented after you open and close a lot of applications and eventually there aren't any holes left to open any applications. So shutting down once a day takes care of that. This is not malarky. I have a memory mapper application that actually shows how my memory gets fragmented.

So, you OS X weenies, does OS X defrag RAM in the background so that it's not a problem in OS X?

Message #7 - Posted 2005/05/20 - clvrmnky

On 20/05/2005 12:42 PM, roj wrote:

I've heard it's a good idea to shut down now and then, as the machine

does some behind the scenes cleaning up and the like in the boot process.

In OS 9, RAM gets fragmented after you open and close a lot of applications and eventually there aren't any holes left to open any applications. So shutting down once a day takes care of that. This is not malarky. I have a memory mapper application that actually shows how my memory gets fragmented.

So, you OS X weenies, does OS X defrag RAM in the background so that it's not a problem in OS X?

Different memory model completely. Modern operating systems use a variety of techniques to maintain contiguous chunks of heap. Just let the kernel do it's job and don't worry about it.

I bigger worry is application memory leaks eating up heap over time, or in-kernel processes like device drivers corrupting memory. There is always room for improvement here, but not much a user can do to keep a bad driver from causing a panic.

Message #8 - Posted 2005/05/21 - David C.

"roj" <Alternity@EV1.net> writes:

In OS 9, RAM gets fragmented after you open and close a lot of applications and eventually there aren't any holes left to open any applications. So shutting down once a day takes care of that. This is not malarky. I have a memory mapper application that actually shows how my memory gets fragmented.

So, you OS X weenies, does OS X defrag RAM in the background so that it's not a problem in OS X?

OS X doesn't use a memory model where this is even a possible concern.

All memory is virtual. Every process gets its own virtual-address space that is contiguous. Pages of physical RAM and/or swap space (I believe 4K per page) are assigned to this address space as needed.

If you would examine the physical allocation, you'd find it incredibly fragmented, but you'd see that after a very short time (maybe even within minutes of power-on). This doesn't cause any problems, like it does on systems like OS 1-9, that do not use a demand-page memory model.

-- David

Message #9 - Posted 2005/05/21 - David C.

jeffrey lohn <jlohn@nyc.rr.com> writes:

would appreciate advice on whether i should shut the computer down at night... or just let it go to "Sleep" with the "Sleep after 20 minutes of inactivity" choice in the Energy saver control panel? which means if i use the computer every day, i would never shut it down?

I only shut down when I'm going to be away from home for more than two days. Otherwise, the system remains on.

I do turn off the monitor when I'm away, however. CRT's consume a lot of power. If you have an LCD display, the backlight does have a limited lifespan - turning it off when not in use will make it last longer.

I do log-out when I'm done with it. Although OS X has no problem staying on 24/7, some apps have bugs that will cause things to get flaky if they are running constantly. (The Finder used to have had this problem, but Apple may have fixed it by now.) When you log-off, all user-level processes terminate, leaving only the system processes running.

If you are running a pre-X version of Mac OS (1-9), then you should reboot or shut down from time to time. Others have already explained why.

-- David

Message #10 - Posted 2005/05/21 - roj

I do turn off the monitor when I'm away, however. CRT's consume a

lot

of power. If you have an LCD display, the backlight does have a

limited

lifespan - turning it off when not in use will make it last longer.

I'm more concerned with waste heat from my CRT than power consumption. (of course they are related) My 20 inch CRT pumps out a lot of heat. The top of it makes a good hand warmer in the wintertime. If I leave the CRT on for a long time, the temperature in my computer room will be about 6 degrees warmer than the rest of the house. So if I ain't looking at it, the monitor is off.

Message #11 - Posted 2005/05/22 - jeffrey lohn

Previously, David C. wrote:

"roj" <Alternity@EV1.net> writes:

In OS 9, RAM gets fragmented after you open and close a lot of applications and eventually there aren't any holes left to open any applications. So shutting down once a day takes care of that. This is not malarky. I have a memory mapper application that actually shows how my memory gets fragmented.

So, you OS X weenies, does OS X defrag RAM in the background so that it's not a problem in OS X?

OS X doesn't use a memory model where this is even a possible concern.

All memory is virtual. Every process gets its own virtual-address space that is contiguous. Pages of physical RAM and/or swap space (I believe 4K per page) are assigned to this address space as needed.

If you would examine the physical allocation, you'd find it incredibly fragmented, but you'd see that after a very short time (maybe even within minutes of power-on). This doesn't cause any problems, like it does on systems like OS 1-9, that do not use a demand-page memory model.

-- David

i would say roughly once a week when , in the morning , when i go to wake my asleep(not shut down) computer up, it's completely frozen. i have to shut the power... and then boot it up.
any suggestions about this problem?? i'm running OS 10.2.8 and have only 256 mb of RAM on board (it's a 1.25 FW800 dual)

Message #12 - Posted 2005/05/22 - Bob Harris

Previously, jeffrey lohn wrote:

Previously, David C. wrote:

"roj" <Alternity@EV1.net> writes:

In OS 9, RAM gets fragmented after you open and close a lot of applications and eventually there aren't any holes left to open any applications. So shutting down once a day takes care of that. This is not malarky. I have a memory mapper application that actually shows how my memory gets fragmented.

So, you OS X weenies, does OS X defrag RAM in the background so that it's not a problem in OS X?

OS X doesn't use a memory model where this is even a possible concern.

All memory is virtual. Every process gets its own virtual-address space that is contiguous. Pages of physical RAM and/or swap space (I believe 4K per page) are assigned to this address space as needed.

If you would examine the physical allocation, you'd find it incredibly fragmented, but you'd see that after a very short time (maybe even within minutes of power-on). This doesn't cause any problems, like it does on systems like OS 1-9, that do not use a demand-page memory model.

-- David

i would say roughly once a week when , in the morning , when i go to wake my asleep(not shut down) computer up, it's completely frozen. i have to shut the power... and then boot it up.
any suggestions about this problem?? i'm running OS 10.2.8 and have only 256 mb of RAM on board (it's a 1.25 FW800 dual)

I used to run into this kind of frozen problem when I was using some 3rd party screen saver modules. I stopped using them and have not experienced the problems since.

Another possibility is that it is a hardware problem. Do you have any 3rd party memory installed. While most 3rd party memory is reliable (and I use it all the time), a bad module does happen, and has been the cause of many a Mac's hardware problems. While most bad memory fails in a big way (system crash), that does not mean it can not fail in a very marginal way.

Having said all of this about memory, does not mean you have a memory problem, just that you might keep it in mind as a possibility.

Bob Harris

Message #13 - Posted 2005/05/22 - Bob Harris

Previously, jeffrey lohn wrote:

Previously, David C. wrote:

"roj" <Alternity@EV1.net> writes:

In OS 9, RAM gets fragmented after you open and close a lot of applications and eventually there aren't any holes left to open any applications. So shutting down once a day takes care of that. This is not malarky. I have a memory mapper application that actually shows how my memory gets fragmented.

So, you OS X weenies, does OS X defrag RAM in the background so that it's not a problem in OS X?

OS X doesn't use a memory model where this is even a possible concern.

All memory is virtual. Every process gets its own virtual-address space that is contiguous. Pages of physical RAM and/or swap space (I believe 4K per page) are assigned to this address space as needed.

If you would examine the physical allocation, you'd find it incredibly fragmented, but you'd see that after a very short time (maybe even within minutes of power-on). This doesn't cause any problems, like it does on systems like OS 1-9, that do not use a demand-page memory model.

-- David

i would say roughly once a week when , in the morning , when i go to wake my asleep(not shut down) computer up, it's completely frozen. i have to shut the power... and then boot it up.
any suggestions about this problem?? i'm running OS 10.2.8 and have only 256 mb of RAM on board (it's a 1.25 FW800 dual)

Oh yea. I also had my freezes on 10.2. I'm running 10.3 now, and as soon as my company makes the latest Cisco VPN client available, I intent to upgrade to Tiger.

I just saw a deal posted on <http://dealmac.com>. Panther for $30. Maybe now is the time to upgrade one rung on the OS version ladder :-)

Bob Harris

Message #14 - Posted 2005/05/22 - Paul Russell

David C. wrote:

OS X doesn't use a memory model where this is even a possible concern.

All memory is virtual. Every process gets its own virtual-address space that is contiguous. Pages of physical RAM and/or swap space (I believe 4K per page) are assigned to this address space as needed.

If you would examine the physical allocation, you'd find it incredibly fragmented, but you'd see that after a very short time (maybe even within minutes of power-on). This doesn't cause any problems, like it does on systems like OS 1-9, that do not use a demand-page memory model.

Actually the lack of page colouring in OS X does cause some performance problems, but for most people this is not a big deal.

Paul

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