Is quad core noticeably better than dual core?

[Robert Maxwell]

moving between them (if swap is being used)

If you have a 64-bit OS and enough RAM, this should rarely be a problem.

Of course, on Windows it is a problem anyway, because Windows is swap-happy. Someone claimed there was a way to alleviate that, but declined to give specifics. I haven't been able to find such a setting on my own.

If you have enough RAM, you can disable swap ("virtual memory") entirely:

Start -> Control Panel -> System -> Advanced (tab) -> Performance (Settings) -> Advanced (tab) -> click the "Change" button under "Virtual Memory".

In the menu that brings up, select "No paging file". Save and (possibly) reboot. Good to go! No more swap. Windows will, naturally, complain if you do run out of real memory and things will abruptly quit working. But if you have several gigs of RAM, this shouldn't be a problem unless you like to run Firefox with a hundred open tabs.

 

[Lindley]

Ah, but that's overkill. Virtual Memory is a good thing, especially for a software developer. I merely wish Windows would be more conservative in its medium-term scheduling policy.

 

[Robert Maxwell]

Ah, but that's overkill. Virtual Memory is a good thing, especially for a software developer. I merely wish Windows would be more conservative in its medium-term scheduling policy.

Virtual memory is just swap. That's all it is, all it does, all it's good for: you need more memory than your system physically has.

Am I missing something here? I'm a programmer, too, but I don't see what virtual memory is good for except slowing down your system when you really just need more RAM.

In any case, I don't know any way to "tweak" the performance or behavior of virtual memory. What Windows gives you in that menu is pretty much it.

 

[Rii]

Why has no one suggested "faster disks"? While a speedy CPU, multiple cores, and ample RAM will give your system a lot of "potential," people tend to ignore the remaining bottleneck: disk speed. A lot of what your PC does is disk-bound: loading programs, moving between them (if swap is being used), opening/saving files, etc. While you're configuring a computer, consider opting for a 10,000 RPM drive or even a RAID array. You'd be surprised how often system speed is perceived as "slow" because of subpar disks.

The primary advantage 10/15K RPM HDDs have over their slower counterparts is seek speed, and in that respect SSDs are even better.

SSD sustained transfer rates can also compare quite favourably with those of 10K RPM HDDs, and perhaps more significantly their performance doesn't vary according to the area of the disk that's being written to or read from as with a conventional HDD. Of course some of the latest 7200 RPM HDDs can also match older 10K RPM drives in sustained transfer rates owing to their higher data densities.

If only it weren't for that pesky $/GB thing.

 

[Robert Maxwell]

Yeah, that's why I stopped short of suggesting solid-state: price. You could probably assemble a screaming fast RAID 0 array for considerably less money.

 

[Lindley]

Virtual memory is just swap. That's all it is, all it does, all it's good for: you need more memory than your system physically has.

Am I missing something here? I'm a programmer, too, but I don't see what virtual memory is good for except slowing down your system when you really just need more RAM.

In any case, I don't know any way to "tweak" the performance or behavior of virtual memory. What Windows gives you in that menu is pretty much it.

What I'd like is a way to tell the MTS, "don't swap this program unless you really, really, really have to." Say, the OS, maybe. Or right-click menus----I'd love it if it didn't take 30 seconds to bring those up just 'cause the machine is a bit busy.

Virtual Memory also handles the allocating of my physical 4GB to 32-bit processes which can't handle that much by themselves. That's the part of it I value.

 

[Robert Maxwell]

Disabling the paging file doesn't disable anything else. It just forbids Windows from swapping anything out to disk. It should not affect scheduling, memory allocation, processor affinity, or anything like that.

 

[Lindley]

Well, I'll give a shot and see what happens.

 

[Rii]

Yeah, that's why I stopped short of suggesting solid-state: price. You could probably assemble a screaming fast RAID 0 array for considerably less money.

There's something about deliberately increasing the risk of data loss that's never sat well with me.

 

[Robert Maxwell]

Yeah, that's why I stopped short of suggesting solid-state: price. You could probably assemble a screaming fast RAID 0 array for considerably less money.

There's something about deliberately increasing the risk of data loss that's never sat well with me.

Data loss is irrelevant if you make frequent, offsite backups.

 

[Daedalus12]

Virtual memory is just swap. That's all it is, all it does, all it's good for: you need more memory than your system physically has.

Am I missing something here? I'm a programmer, too, but I don't see what virtual memory is good for except slowing down your system when you really just need more RAM.

In any case, I don't know any way to "tweak" the performance or behavior of virtual memory. What Windows gives you in that menu is pretty much it.

What I'd like is a way to tell the MTS, "don't swap this program unless you really, really, really have to." Say, the OS, maybe. Or right-click menus----I'd love it if it didn't take 30 seconds to bring those up just 'cause the machine is a bit busy.

Virtual Memory also handles the allocating of my physical 4GB to 32-bit processes which can't handle that much by themselves. That's the part of it I value.

AFAIK the tendency for windows to swap too eagerly was fixed in Vista.

 

[Rii]

Vista grinds away at the HDD for ages upon startup as it insists on filling every inch of available memory with programs it thinks you might want to load based on previous usage history. It doesn't bother me, but it's amusing that with 4GB of RAM in this PC the Task Manager never displays more than 50MB free.

 

[JoeZhang]

Vista grinds away at the HDD for ages upon startup as it insists on filling every inch of available memory with programs it thinks you might want to load based on previous usage history. It doesn't bother me, but it's amusing that with 4GB of RAM in this PC the Task Manager never displays more than 50MB free.

If that's the case, there is something wrong with your machine.

 

[Rii]

Vista grinds away at the HDD for ages upon startup as it insists on filling every inch of available memory with programs it thinks you might want to load based on previous usage history. It doesn't bother me, but it's amusing that with 4GB of RAM in this PC the Task Manager never displays more than 50MB free.

If that's the case, there is something wrong with your machine.

No there isn't.

http://www.codinghorror.com/blog/archives/000688.html
http://en.wikipedia.org/wiki/Windows_Vista_I/O_technologies#SuperFetch

 

[Daedalus12]

but it's amusing that with 4GB of RAM in this PC the Task Manager never displays more than 50MB free.

So what if the task manager never displays more than 50 MB free? Unused memory is wasted memory. On my Linux box with 4 gb of memory there is usually only 100 mb of free memory. This box has been up for the last 140 days. No performance issues and no lag whatsoever. No excessive swap to the disk of note.

 

[Lindley]

Well, Linux boxes seem to be much better about the whole swapping thing in general.

 

[Robert Maxwell]

but it's amusing that with 4GB of RAM in this PC the Task Manager never displays more than 50MB free.

So what if the task manager never displays more than 50 MB free? Unused memory is wasted memory. On my Linux box with 4 gb of memory there is usually only 100 mb of free memory. This box has been up for the last 140 days. No performance issues and no lag whatsoever. No excessive swap to the disk of note.

This person is correct. Program caching is a good thing. It's only if it has a lousy predictor that it becomes a pain. Hell, I tend to reserve 0.5-1GB of memory for a RAMdisk for all my most frequently used files. Makes things a lot faster, at least for those files.

 

[Rii]

Yeah, that's why I stopped short of suggesting solid-state: price. You could probably assemble a screaming fast RAID 0 array for considerably less money.

I had a little poke around to check the current state of the market, OCZ claims read performance of around 140MB/sec on their new "Core" line of SSDs and this appears to be backed up by initial testing. Even allowing for the possibility that the numbers are a little inflated, that's right up there with peak read performance on the current benchmark 15K RPM Seagate Cheetah, which of course drops to well under 100MB/sec on the inner tracks. Couple that with the seek advantages of SSDs and I'd say the days of the mechanical HDD for performance sensitive applications are definitely numbered.

 

[Capt. Vulcan]

I've got a quad core and it's a big difference for me. I can convert video, transfer files, and play halflife 2 at the same time and there's hardly a hiccup. If you like to multitask it'll be great for you.

 

[Alaedhros]

Why has no one suggested "faster disks"?

In the post directly above the one where you made this statement, I mentioned both disk speed and disk cache size.

Well, I'll give a shot and see what happens.

Should be interesting. Post an update to let us know what happens!

This person is correct. Program caching is a good thing.

I'm not sold just yet. On a box with 2+ GB where you are the sole user, yeah, I can see it. But on a box with just 1 GB (like my personal computer), or on a box that you're sharing with other people, it doesn't seem as viable. Now, I don't know what my box is doing with the RAM that it uses, but between the core services, GNOME, and "essential applications" like Firefox, there's not oodles of memory left, and my instinct is that what is left should remain free. Perhaps I'm incorrect?