SSD Advantage?

[sreilly]

I have been watching the solid state drive industry for a while now and as prices fall for this new technology I continue to wonder if it is worth the price for what we do as far as processing. What I see as an advantage is the speed in which large amount of data is capable of being read and since starting to use a STL-11000M camera with individual calibrated file sizes of about 25MB per frame I suspect this would be faster in processing. My typical images are 12-20 hours of usable data usually consisting of 20 minute subs. So any given image may be a result from 36-60 25MB files and these are just the light frames not to mention the calibration frames and the amount of space consumed for processing enabling of undo and redo.

So, in real world times, is there a worthwhile increase in speed justifying the increased cost? A typical 256GB SSD is about $350-400 from what I've seen and I've read about their increase in read/write speed, low power consumption resulting in lower heat generation. Their MTF rate is quite a bit larger as there are no moving parts you would expect but then it isn't reflected in their warranty which I would expect. They aren't near as susceptible to shock as standard HDs so that danger is greatly reduced but then they also don't have the capacity that SATAs have. I think the largest SATA 6/GBs drive I remember seeing is 3TBs.

Which also makes me wonder what is the best approach for using one of these SSDs. If you use it as your primary boot drive (C), all your programs will be on that drive. Currently my Windows 7 Pro 64 bit system is using 133GBs of space and that doesn't have my stored raw images. I guess you could transfer your working raw data to the SSD, process the images and then store the calibrated and final master images on an additional data drive.As is now I have my image data on drive D and that folder consumes 179 GBs but that is all of this years data so far and about 1/2 of last years. Needless to say I can see that 256GB SSD drive filling rather quickly.

Any thoughts?

[Nocturnal]

An SSD will speed up disk-bound anything. Processes that are CPU bound will not benefit. I don't know if image calibration is disk bound in PI or not. If your CPU isn't constantly pegged during the process then there's a good chance that an SSD will speed things up. I have one in my system as the C: drive. I do all my image processing on it and sync c:\astroimaging to g:\astroimaging (a large HDD) which in turn gets sync'd to my NAS. I remove projects that re done from c:\ and they stay on the two other destinations.

Needless to say the saving and reading of images and projects in PI goes faster with an SSD. Stepping through the history also goes quicker because swap files read faster.

Personally I think an SSD is a no-brainer improvement for any PC if you have a few hundred bucks to spend. Use it as your C drive and you benefit beyond just PI.

[RBA]

What about wearing off the SDD through multiple read/writes? I know the numbers are insanely big and they can last quite a while - I should know, as my laptop in the field only has an SSD and I've had it for 4 years already, but still, something to consider...

[Nocturnal]

No, not something to consider. Every part in your computer can fail. Protect your data, make backups.

[chris.bailey]

I use a much abused 3 year old Panasonic Toughbook in the obsy. I just replaced the HD with an SSD (the laptops a bit long in the tooth but expensive to replace) and the difference is staggering. Used to take about 5 minutes to fully boot up, now takes 30 seconds. I only use it for imaging and then transfer data to a more secure environment.

[RBA]

No, not something to consider. Every part in your computer can fail. Protect your data, make backups.

I wouldn't disregard it so quickly. As it seems, cheap SSDs (MLC-based for example) cannot handle nearly as many writes as the more expensive ones. Under an average load, a cheap SSD's life expectancy may not last the time it takes you to willingly replace it. This is not just about failure, but about a somewhat hard-fixed working life. Still, more expensive SSDs should be able to give you many years of excellent performance, blowing away the performance of the very best hard drives out there, and all the way to the point you upgrade because you want to. But I wouldn't openly state that this is something that should be completely disregarded.

Anyway, this is, at least, my understanding. Next time I go shopping for an SSD I will definitely look into their life expectancy, to be sure I buy something more reliable than the neighbor who just tried to save a few bucks and got the cheap one. So far, none of my flash cards or SSD drives have had any issues and maybe I'm too paranoid, but I'd rather keep an eye on those things, why not?

[Christoph Puetz]

Hallo,
I think SSD could improve the speed of IO-intensive operations in PI, ***BUT*** (as it was said before) the lifetime of read/write operations is limited compared to normal disks.
In order to improve the speed of PI, I would therefore:
- in PI go to Global Preferences->Directories and Network. Add some more directories, but take care that they should be on different physical devices.
- spend your computer much more memory whenever possible. I have 8GB of ram and it could be twice as much to get more performance.

If you would buy an ssd and place all the swap files on it, it would fail rather fast (as i heard, ssd's "only" are designed for a million of write operations).

christoph

[georg.viehoever]

A well respected computer magazine in Germany (ct) has tested SSDs for wear out. They have not been able to provoke any errors, even after weeks of continuous writing. So I would not worry too much. A significant problem was that certain disks slowed down considerably after a while, presumably due to deficits in their wear level algorithms. Make sure you buy a modern SSD with a modern controler, and you are on the save side.

You should make backups anyway (even if you dont use SSDs  ).

Georg

[Christoph Puetz]

Georg is right.  SSD technology has been much improved 8)
I just read again about new SSDs techniques in some internet test resources.
You should take care that you use SSDs with SLC-chipset.
They should reach write operations up to 1.000.000 Gigabytes in sum (or about 500GByte per day for 5 years).

SSDs with MLC-chipset are cheaper, but are only guaranteed up to 20 GBytes per day.

If you will use SSDs under Windows OS you should deactivate defragmentation, prefetch and super fetch functions for these
devices !