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How often to shut down?

My battery is at a 2 cycle count and I shut it down when I need to do so, but nothing wrong with my battery. I've used it primarily when it's plugged in, but that's just me. I've had the MB battery give out on me one time and I've been gun-shy ever since....
 
IJ Reilly said:
Anyway, you're not correct about swap files. OSX creates them, they do build up, they do slow down performance, often noticeably -- and they don't go away until you restart the Mac. Fact, fact, fact and fact.
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I've never had slow performance or swap file problems on my Mac, even going months without shutting down. Fact. Where are the "facts" that support your argument that Macs suffer reduced performance from not shutting down? Links, please.
 
GGJstudios said:
I've never had slow performance or swap file problems on my Mac, even going months without shutting down. Fact. Where are the "facts" that support your argument that Macs suffer reduced performance from not shutting down? Links, please.
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I have seen it on every Mac I have owned, especially the older, slower ones. The Mac starts to get slow, I see the pinwheel more often. I check the VM directory and find four or five swap files. I restart, the slowdown is gone along with swap files. If you're trying to say that OSX doesn't create VM swap files, then you are wrong. It creates huge VM swap files, more and larger with time. If you're trying to say something else, then I don't know what it is.
 
Ya know, for me it's hard to tell if I actually experience a slow down, but when I think that I experience one I just run ONYX. Of course, that does force me to restart.... so it's a conundrum. Oh well, restarting is not an issue. I shut notebook down each evening and restart in the morning.

Maybe it's just because I like how starting up is fast on a Mac; something that I never could do in my PC years :p
 
IJ Reilly said:
I have seen it on every Mac I have owned, especially the older, slower ones.
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Ahh, so it's just your personal experience, not "fact". That clears it up.
IJ Reilly said:
If you're trying to say that OSX doesn't create VM swap files, then you are wrong.
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No, I didn't say that OS X doesn't create swap files. I said it's not necessary to reboot OS X to prevent decreased performance. You may also be suffering from a RAM deficiency.
IJ Reilly said:
If you're trying to say something else, then I don't know what it is.
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Perhaps it's better not to reply to posts until you understand what you're replying to.
 
GGJstudios said:
Ahh, so it's just your personal experience, not "fact". That clears it up.
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No, this subject is extensively documented, and personal experience backs it up. This has also been a frequent topic of discussions in this forum over the years. Mainly it is discussed in terms of pageins/pageouts, a number which can be seen in Activity Monitor -- but this is really just another way of measuring the same activity -- OSX paging to VM swap files. Paging in and out results in a performance penalty, because accessing disk-based RAM is not as fast as accessing physical RAM. This is well known, and until today, I'd never heard anyone dispute it.

No, I didn't say that OS X doesn't create swap files. I said it's not necessary to reboot OS X to prevent decreased performance. You may also be suffering from a RAM deficiency.
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A very puzzling remark. Of course VM swap files are caused by insufficient RAM. That is their entire purpose. VM swap files are persistent and are created when physical RAM is exceeded. They aren't deleted until you restart the Mac (some but not all are deleted with a logout).

Perhaps it's better not to reply to posts until you understand what you're replying to.
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Funny, that's what I was about to say. Anyway, read.

http://www.thexlab.com/faqs/lackofram.html
 
IJ Reilly said:
A very puzzling remark. Of course VM swap files are caused by insufficient RAM. That is their entire purpose. VM swap files are persistent and are created when physical RAM is exceeded. They aren't deleted until you restart the Mac (some but not all are deleted with a logout).
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if its so important then why do so many mac users say that they dont have to restart? i think that is you that has this problem and with all you know about the issue you should be smart enough to realize that. you could be doing something different than a lot of other mac users that requires you to have to restart your computer. im not going to be like you and say that i doesnt help you and that is great that it does. the same way that when i reinstall the OS it runs faster FOR ME.

Funny, that's what I was about to say.
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your so clever. keep it up.:rolleyes:
 
IJ Reilly said:
Mainly it is discussed in terms of pageins/pageouts, a number which can be seen in Activity Monitor -- but this is really just another way of measuring the same activity -- OSX paging to VM swap files. Paging in and out results in a performance penalty, because accessing disk-based RAM is not as fast as accessing physical RAM. This is well known, and until today, I'd never heard anyone dispute it.
Click to expand...
You appear to be confusing the benefits of RAM vs rebooting. No one is disputing that having insufficient RAM will cause increased paging activity and performance degradation. However, rebooting will not resolve this issue. If you reboot and then launch the same applications that exceed physical RAM, you'll be right back to paging again. The resolution is to buy more RAM, not reboot. If your workload temporarily causes an increase in paging activity, the paging will stop when the workload is reduced. Windows was known to not effectively release RAM and make it available to other apps when the app that was using it was closed. This is not the case with OS X.
 
GGJstudios said:
You appear to be confusing the benefits of RAM vs rebooting. No one is disputing that having insufficient RAM will cause increased paging activity and performance degradation. However, rebooting will not resolve this issue. If you reboot and then launch the same applications that exceed physical RAM, you'll be right back to paging again. The resolution is to buy more RAM, not reboot. If your workload temporarily causes an increase in paging activity, the paging will stop when the workload is reduced. Windows was known to not effectively release RAM and make it available to other apps when the app that was using it was closed. This is not the case with OS X.
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No, I'm not confusing these things, but I think you might be. Having insufficient physical RAM for whatever applications you are running will create VM swap files. At that point, OSX will have to flog your drive for data that it would normally store in physical RAM. That is when the paging in and out occurs. The important fact you may not be considering is that these files are persistent. They don't get deleted, and as nearly as I can tell, OSX continues to use them for as long as they exist. Rebooting deletes them.

Probably the geekiest thing I do on my Mac is monitor my VM swap file directory. With 2GB of RAM I can normally run for several days, even a week, without creating more than the one default swap file. Eventually, I will see two, then three or four -- and they double in size at every other step from 64Mb, quickly growing to 1Gb and more. How fast this happens depends on what applications I run. The worst RAM hog I use regularly is iPhoto. I notice it tends to grab a lot of VM when I edit photos. One, two or three VM files don't seem to produce any noticeable hit in performance. Beyond that, the slowdown becomes more evident. Reboot, problem gone.

I'd agree that if you see these files multiplying rapidly and often, then more RAM is in order. But even on systems with maximum RAM can have this issue, so it's worth keeping in mind. Call occasional rebooting a poor-man's solution if you like. The important fact is, it works.

I don't know how Windows handles VM, and I don't really care. That is not important to this discussion.
 
IJ Reilly said:
...Having insufficient physical RAM for whatever applications you are running will create VM swap files. ... these files are persistent. They don't get deleted, and as nearly as I can tell, OSX continues to use them for as long as they exist. Rebooting deletes them.
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The swap files are stored on your hard drive, so unless you have insufficient free HD space, having a larger swap file will have no effect whatsoever on system performance, compared to a smaller swap file. What impacts performance is the actual paging itself, not the size of the file on the drive. If you've previously run apps that involved significant paging and your swap files are large, but you're no longer running resource-intensive apps that require more than the RAM you have, OS X is no longer paging and no longer accessing those swap files. Their size is irrelevant. Rebooting will not increase system performance.
 
It does the system good to shutdown every once in a while. It gives the system a refresh in other words. Give your poor mac a rest!! :p I shutdown my mac when I'm not gong to use it for a Long period of time.
 
Believe it or not, simply having your computer on is putting "wear" on the machine. Electricity is flowing through it, the drive is spinning, fans are spinning, heat is being generated, etc.
Unless you really have a reason to, or simply can't stand the 30-60 seconds it takes for your computer to boot up, why leave it on for long periods of time when not using it?
 
NickM said:
Believe it or not, simply having your computer on is putting "wear" on the machine. Electricity is flowing through it, the drive is spinning, fans are spinning, heat is being generated, etc.
Unless you really have a reason to, or simply can't stand the 30-60 seconds it takes for your computer to boot up, why leave it on for long periods of time when not using it?
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Drives and fans don't spin and electricity usage and heat is virtually nonexistant during sleep. It's not putting wear on your system to have it sleep vs shutting it down.
 
GGJstudios said:
Drives and fans don't spin and electricity usage and heat is virtually nonexistant during sleep. It's not putting wear on your system to have it sleep vs shutting it down.
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Ahh...guess I should have read the first post more closely.
I thought it was simply a Shut Down vs. Not Shut Down argument.
As for Sleep mode, I don't really ever use it... only when I'm using the computer somewhere, where I need to move locations, and I know that I'll be right back on it.
Other than that, I shut her down if I'm not using it and nothing is downloading.
 
awpitchy said:
It does the system good to shutdown every once in a while. It gives the system a refresh in other words.
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awpitchy said:
It's common sense isn't it really. I'm sure you could find a fact to support that.
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No, it's not "common sense". Exactly how do you think "It does the system good" to shutdown? What exactly does it mean to "give the system a refresh"? You're making it up as you go along, and you have no facts to support your statement.
 
GGJstudios said:
The swap files are stored on your hard drive, so unless you have insufficient free HD space, having a larger swap file will have no effect whatsoever on system performance, compared to a smaller swap file. What impacts performance is the actual paging itself, not the size of the file on the drive. If you've previously run apps that involved significant paging and your swap files are large, but you're no longer running resource-intensive apps that require more than the RAM you have, OS X is no longer paging and no longer accessing those swap files. Their size is irrelevant. Rebooting will not increase system performance.
Click to expand...

A nearly full hard drive will make the situation drastically worse, but the very fact that the OS is having to access the drive to retrieve data it would normally store in physical RAM slows the process down because physical RAM is much faster than a hard drive. According to those who've made a study of this, the VM disk flogging problem can be mitigated some by storing the VM swap files on a separate drive or partition. This sounds like a dangerous hack to me, but apparently some are motivated to do it.

Neither you nor I know precisely how OSX handles swap files, or even more importantly, why they are persistent. But they are persistent, they are not released when no longer needed, and they do multiply, and grow. Why they do this, and why it causes a performance hit on a drive with plenty of free space, I don't pretend to know. However, from actual experience, I know that deleting them does make a difference.

GGJstudios said:
There are no facts to support that statement.
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Except for the ones you are ignoring.
 
IJ Reilly said:
A nearly full hard drive will make the situation drastically worse, but the very fact that the OS is having to access the drive to retrieve data it would normally store in physical RAM slows the process down because physical RAM is much faster than a hard drive. According to those who've made a study of this, the VM disk flogging problem can be mitigated some by storing the VM swap files on a separate drive or partition. This sounds like a dangerous hack to me, but apparently some are motivated to do it.

Neither you nor I know precisely how OSX handles swap files, or even more importantly, why they are persistent. But they are persistent, they are not released when no longer needed, and they do multiply, and grow. Why they do this, and why it causes a performance hit on a drive with plenty of free space, I don't pretend to know. However, from actual experience, I know that deleting them does make a difference.
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just a very simple question then. why dont i and many others have this problem?

i haven't shutdown or restarted my computer in 2.5 weeks and i have noticed no slowdown. but i wanted to test your theory. so i did some heavy audio editing with pro tools, shut down the computer for an hour (watched House MD, great show). i turned it back on did the exact same edits and browsing and there was no difference in speed.

how do you explain this?
 
IJ Reilly said:
...why they are persistent. But they are persistent, they are not released when no longer needed, and they do multiply, and grow. Why they do this, and why it causes a performance hit on a drive with plenty of free space, I don't pretend to know.
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Unlike most UNIX-based operating systems, Mac OS X does not use a preallocated swap partition for virtual memory. Instead, it uses all of the available space on the machine’s boot partition. It effectively manages RAM, releasing memory that is no longer used, making it available to other apps. The fact that it hangs onto disc space used for paging has no impact on system performance.

Getting back to the original thread discussion: There is no disadvantage to using sleep vs shut down on a regular basis. Shutting down will NOT improve your system performance, just as sleep will NOT degrade it.
 
GGJstudios said:
...Shutting down will NOT improve your system performance, just as sleep will NOT degrade it.
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I think something that should be said here is that "shutting down" may not help, but wording is critical; restarting, or after a shutdown starting up, a Mac does clear some files.

Sometimes those files can make a difference.
 
GGJstudios said:
Unlike most UNIX-based operating systems, Mac OS X does not use a preallocated swap partition for virtual memory. Instead, it uses all of the available space on the machine’s boot partition. It effectively manages RAM, releasing memory that is no longer used, making it available to other apps. The fact that it hangs onto disc space used for paging has no impact on system performance.

Getting back to the original thread discussion: There is no disadvantage to using sleep vs shut down on a regular basis. Shutting down will NOT improve your system performance, just as sleep will NOT degrade it.
Click to expand...

It does have an impact on system performance, based on years of observation. I don't know why, but then I don't pretend to know why, whereas you are pretending to know that it doesn't, without I have to notice, the links to source as you have demanded from me.

I have noticed this being less of an issue with recent Macs, but again, I don't know if it's the speed of the newer Macs, changes to Leopard, or some other factor.
 
Whew this thread is vicious. I'll present my conclusions, take it or leave it: restarting can help. Sometimes it will be noticeable, sometimes it will not. I do not believe that restarting does not help anything, it goes against a lot of other information out there, not to mention a ton of user feedback.

Bottom line, as I see it: restarting does not hurt and in fact can help sometimes, shutting down a computer at night saves energy and eliminates heat, which over time can hurt hardware, especially in laptops. Case closed.
 
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