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miragetetra
12-22-2011, 11:03 PM
Heya all,

So I'm getting a G73SX soonish and I happen to have a spare SSD that might do well in the new machine. I'm thinking of using the SSD as my main drive and the 500gb HDD as my storage (as well as home for older games) and it dawned on me, which disk should I use for my virtual memory?

The machine will have 16gbs of memory and the SSD is a 160gb drive.

If I put the virtual memory on the SSD, then a little more then a third of the drive will be virtual memory.

If I put it on the HDD I'm not sure how that will affect performance (maybe it will negate having an SSD?).

So overall not sure which direction I should go here.

Simba7
12-22-2011, 11:06 PM
BAD IDEA!!! Do NOT put your swap file on an SSD, unless you want to kill it rather quickly.

miragetetra
12-22-2011, 11:08 PM
That was my thoughts as well. As well as the issue of the Virtual Memory file taking up most of the SSD capacity. That said, how much of a hit will the machine take if the Virtual memory file is on the HDD?

Simba7
12-22-2011, 11:11 PM
Not alot. I have 24GB in my G53SX and I never get close to touching the swap.

It all depends on how much stuff you run.

AQUASTEVAE
12-23-2011, 01:18 AM
yeah, i have a 256 gb crucial m4 as my os drive on my g74sx, and i put my virtual mem on the 750 hdd. this works absolutely perfectly. the swapfile will wear out a ssd, so you don't want it on there. and you should always put it on a partition that isn't going to be used much. most of the time i make a partition just for the virtual memory. that allows it to run unfettered. with this setup, my system is blazing fast. good luck, and post back once you have set it all up.

BrodyBoy
12-23-2011, 01:36 AM
HSo I'm getting a G73SX soonish and I happen to have a spare SSD that might do well in the new machine. I'm thinking of using the SSD as my main drive and the 500gb HDD as my storage (as well as home for older games) and it dawned on me, which disk should I use for my virtual memory?

The machine will have 16gbs of memory and the SSD is a 160gb drive.

If I put the virtual memory on the SSD, then a little more then a third of the drive will be virtual memory.

If I put it on the HDD I'm not sure how that will affect performance (maybe it will negate having an SSD?).

So overall not sure which direction I should go here.
I'm going to diverge from the opinions offered here.....

First, with 16Gb RAM, you only need a page file "in name only." That is, you will virtually NEVER use it, but some programs expect to find one when they are configured. Not that they'll ever necessarily use it, but part of their set-up is knowing where it is, and they can get pissy if they don't find one. Therefore, you just need a nominal page file of 1-2Gb, not the 3x that used to be recommended when 1-2Gb RAM was the norm.

Second, there is no harm at all in putting it on your SSD. SSDs use wear leveling algorithms that prevent particular cells from getting used significantly more or less than others. And as mentioned, it's not going to get used anyway.

So go ahead and put it on your SSD. On the rare occasions that it might actually get used, why wouldn't you put it on the next fastest location in your system (after RAM)? SSDs aren't nearly so fragile as some might suggest....they're meant to be used, not babied.

FWIW, I have 1-2Gb page files set up on the SSDs in both my laptops (i.e., 1Gb min, 2Gb max). They work just fine.

fostert
12-23-2011, 02:35 AM
I agree with the BB...a swap partition on an SSD will be rarely used on a machine with a good amount of RAM on it, and SSDs are meant to be used, abused, and thrown away when they can no longer be made to work. No use in preserving it when theres work (games) to be done! When you access a swap often you'll be reading and writing in bursts, the speeds for which are exceedingly fast on an SSD and approach saturating the SATA III bandwidth limit of 6Gb/s (750 MB/s). That really isn't swap anymore by definition...its more like having slow PC-800 RAM in reserve.

miragetetra
12-23-2011, 04:39 AM
Nice, I believe I'll try out BB's config and see how it works out. Actually I'm hoping that the >= 500gb SSD fall down to the $200-$300 range by the end of 2012/2013 so I'm not too concerned about longevity (though I will likely keep this drive for many years to come. Either way, I'm excited to see how the new machine is going to run with this new hardware going in

Simba7
12-23-2011, 07:55 AM
You *might* want to see how well your SSD does on random writes before shifting your swap file to it.

I would still suggest putting your swap on the HDD, even if you barely use it.

---
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MyWS(Phenom II X3 740@3.3GHz,8GB RAM,2TB+1.5TB+1.5TB HDDs,GF GTS250,LG WH12LS30 BD-RE,W7U)
MyNB(Asus G53SX,24GB RAM,2x750GB HDDs,BD-RE,W7U)

fostert
12-23-2011, 11:56 PM
As soon as they come out with 2+TB 2.5 inch HDDs, I'll be getting one (I need that kind of space, yes), and filling the other bay in my G74 with the fastest and smallest SSD I can get. Will make the thing one big swap partition for Linux. Compiling some of my code with gfortran is pushing my physical RAM limit (32GB) and for some programs the linker ld fills 32 GB of physical RAM and spills over to using ~4GB of extra virtual RAM. What should take 15 minutes takes over two hours.

BrodyBoy
12-24-2011, 12:05 AM
@ fostert: From some of your posts, it's clear that you do some pretty high-powered computing! I'm just curious why you do this on a laptop, where it's so much harder (and more expensive) to expand and customize for the demanding work you do? Seems like a desktop would work better.

fostert
12-24-2011, 01:04 AM
Actually until now I have done all my work on desktops (workstations) in my lab. But I travel a few times a year between the Manitoba (where I work) and the Dominion radio astrophysical observatory in BC (where I used to work and continue to collaborate in research projects), and it was always a pain having to prepare for these trips and dump 100s of gigs of data onto an external drive, and then try to anticipate what I'll do while there and try to remember all the other bits of things that I had been working on since my last trip. So I thought I'd try doing all my work on a desktop replacement that I could literally toss into a backpack and go. My next trip is in February, and I will have had the notebook for 4 months then, with all my newest projects on the go that I can literally hop across Canada with whenever I fancy.

I realize that even the fastest notebooks will never touch a desktop in terms of performance, but thanks to gamers (and the desktop replacement market) the difference today is actually alot smaller than it used to be.

Besides the PCs they give visiting researchers at DRAO are ancient, and couldn't even run my updated data processing code which is so unoptimized that it takes sick amounts of ram.

BrodyBoy
12-24-2011, 01:34 AM
Thanks for the explanation...I hope the G74 lives up to your expectations. (And I thin k Asus should be flattered that you chose their machine for this!)

miragetetra
12-25-2011, 09:16 AM
So updating here,

I tried the approach of making a 1gb-2gb Virtual Memory file on the SSD (SSD is my primary drive) and Windows Experience Index rated my drive at 7.4. Then I took the approach expanding that file to it's full size ( 24gb - 48gb) and same thing.

Then I put the swap file on the external HDD and my index rose to 7.5. So at least according to windows, it prefers it's virtual memory on different drives if possible. My guess? It's probably because there is a greater speed up in being able to simultaneously read and write (Asynchronously) versus one at a time

JRd1st
12-25-2011, 12:13 PM
So updating here,

I tried the approach of making a 1gb-2gb Virtual Memory file on the SSD (SSD is my primary drive) and Windows Experience Index rated my drive at 7.4. Then I took the approach expanding that file to it's full size ( 24gb - 48gb) and same thing.

Then I put the swap file on the external HDD and my index rose to 7.5. So at least according to windows, it prefers it's virtual memory on different drives if possible. My guess? It's probably because there is a greater speed up in being able to simultaneously read and write (Asynchronously) versus one at a time
Yup! You guessed correctly. I wonder what that does to the theory that Windows doesn't use the swap file if you have a lot of RAM.

BrodyBoy
12-26-2011, 02:02 AM
Yup! You guessed correctly. I wonder what that does to the theory that Windows doesn't use the swap file if you have a lot of RAM.
Nothing..... ;)