DSS (Deep Sky Stacker) Memory issue

[allenandholmes]

DSS doco mentions that use of the Drizzle option without selection of a "rectangle", will require heavy use of memory and disk space. Yet I have 1.5GB of DDRAM (800MB free for DSS use) and still get an "out of memory" alert at the point where it tries to make the output file. It doesn't seem to make adequate use of virtual disk space. I am running a desktop PC with Windows XP, and shutting down all non-system tasks makes little difference to available memory; though just what is running in the other 700MB needs checking. Thought I'd float this issue here for comment before I rush out to upgrade to 2GB (max. for an HP) of memory. Otherwise, I find DSS a breeze, especially as it's freeware. Over to the forum...

[dpastern]

XP tends to use the hdd cache, rather than real memory from my extensive experience. It's one of the design flaws of the MS windows operating system imho. Linux is far better in terms of memory usage, far more efficient. For that matter, hdd usage as well. Just remember that 32 bit windows will *only* see around 3.2GB of memory anyways, no matter what you do. DSS seems to be quite memory (and core) intensive I've found.

Dave

[allenandholmes]

Thanks for that David. I realise that I was "pushing the envelope" in trying to run DSS under those conditions. I find that Harvey Norman who originally supplied my PC are selling 1GB DDRAM for $129, way below what I paid 2 years ago; it's now on my ever-expanding list of future purchases. The exercise has been somewhat useful in pushing DSS to its limits. Again, I'm grateful for your interest and assistance.
Allen

[dpastern]

You could try other vendors (who are probably cheaper) - I typically use www.itestate.com.au for most of my PC stuff - they're very competitive on pricing, good service, fast delivery. Can't really fault them to be honest. Do you know what type of memory your PC uses?

Dave

[wasyoungonce]

Gads man!...get on to MSY (http://www.msy.com.au/) computers. Look at their parts price list. Lets say you are using DDR1 RAM. 1 GB DDR400 Kingston for $45 from MSY.

Pity your not using DDR2. You can pick up 2GB kingston PC800 RAM for that same price!

[allenandholmes]

I may have mislead you guys. A closer look at my PC shows the original memory (512K, before I slotted in an additional 1GB) is 266MHz DDR SDRAM. I'm not sure how this correction may have affected your responses. A friend has also suggested MSY; I could save myself $50-$80 there, and put it towards MaximDL. :thanx:

[wasyoungonce]

Best to replace all the RAM so as to have it matching. 2 sticks of DDR400 memory from MSY will cost around $88. This is still cheaper than you were looking at in any case.

That should do just fine.

[dpastern]

Yes, MSY is another vendor to try.

Dave

[g__day]

I've seen the same with 6GB of RAM on Win Xp 64 bit - so I'd say it's a DSS issue!

[dpastern]

The only real way of solving this problem and giving yourself enough headroom is to migrate to a x64 bit system. That means an x64 CPU and operating system. That could be a large upgrade cost. In reality, you only need at least a CPU and motherboard, possibly a new PSU, and as much RAM as the new motherboard can use, as well as an x64 o/s.

Old computers are great, but they generally aren't at the cutting edge of performance for high end graphics manipulation. 800mb free for DSS isn't going to give you much headroom, and that's where the problem is occuring imho. Increasing RAM will help, but it's only a bandaid fix imho.

Sorry to be the bearer of bad news. I'm sure others in this thread will disagree with me, but it's my honest advice.

Dave

[wasyoungonce]

Damn...now your scaring me!:question:

[mithrandir]

If DSS is a 32 bit app it won't be able to use more than a couple of GB no matter how much RAM your 64 bit system has.

[allenandholmes]

Good grief! I guess it's time for me to have a rethink; I'd probably be chasing a rainbow (more mem). The main thing is that there isn't some undiscovered function of DSS that could be tweaked to force it to limit its memory usage. Thanks for your assistance folks. :thanx:

[dpastern]

Not in Windows land there isn't Allen. On Linux there's the nice command, although it doesn't directly control the CPU/mem usage. For Windows, a 3rd party application would be needed, try this page:

http://www.snapfiles.com/Freeware/system/fwmemory.html

Try the application, it might help a bit.

Dave

[allenandholmes]

Thanks for the tip Dave. Have installed it running under "normal" mode and it has freed up a little over 20% or around 250MB, and there's no noticeable paging increase so far. As the parliamentary lounge lizard said, "it doesn't get better than this". :thumbsup:
Allen

[dpastern]

Well, that's good news. Every bit helps I guess.

Dave