27" iMac SSD + HDD - Which drive for what, organize for performance?

[lunchfoot]

ok i looked around and found on the low side a cell can take 10k writes before it is done. For the 256GB that comes out to writing a terabyte per day every day for 7 years so i was a little off. nevertheless, this comes out to 11 MB/sec at least and who among you are going to be putting your ssd through that? . It should far outlast any HDD. I'm not worried about wearing mine out. I left my user folder on it, along with apps and OS. This computer is running like a top (21.5" i7 2011). Oh yeah and i have Windows 7 (Bootcamp partition) on it too.

 

[mrfoof82]

1. Everything you can on the SSD.
2. HDD for what won't fit, or does not need the performance (i.e. music, video you consume such as films and TV shows).

That's what I've done. I've created symlinks for parts of my iTunes library that point to the actual directories on the HDD (iTunes U, Movies, Podcasts, TV Shows), so that I don't have to manually shift things around. I also keep virtual machines on the HDD because performance isn't as critical for my use cases, and because they're reasonably large. I also use the HDD as a video scratch disk because there are certainly cases where I'd not notice that I consumed all free disk space.

I think my HDD has ~1400 files/directories on it. Everything else is on the SSD (with ~100GB free after a 64GB Boot Camp partition). No worries. No regrets. Love the performance.

 

[Badger^2]

barefeats tests with Aperture and LR and SSD: http://barefeats.com/wst10c4.html

OTHER INSIGHTS
We tried exporting to both single HDD and single SSD. The export times were identical which tells us that the processing by CPU is the bottleneck. Activity monitor shows that even when the SSD was used, it was loafing along at 6.9MB/s transfer rate and 46 operations per second when it is capable of 40 times that transfer rate and 490 times that many operations per second.

Those stats imply that an iMac Core i7 with at least 8GB of RAM will perform Aperture and Lightroom operations very close to that of a Mac Pro. We will, in fact, do a shootout between various Macs in the next article.


Photoshop, same sorta thing: http://kb2.adobe.com/cps/404/kb404439.html

Solid-state disks
Installing Photoshop on a solid-state disk (SSD) allows Photoshop to launch fast, probably in less than a second. But that speedier startup is the only time savings you experience, because that’s the only time when a lot of data is read from the SSD.

To gain the greatest benefit from an SSD, use it as the scratch disk. Using it as a scratch disk gives you significant performance improvements if you have images that don’t fit entirely in RAM. For example, swapping tiles between RAM and an SSD is much faster than swapping between RAM and a hard disk.

If your SSD doesn’t have much free space (that is, in case the scratch file ever grows bigger than will fit on the SSD), you can add a secondary or tertiary hard disk (after the SSD).

Also, SSDs vary widely in performance, much more so than hard disks. Using an earlier, slower drive results in little improvement over a hard disk.

Note: Adding RAM to improve performance is more cost effective than purchasing an SSD. If money is no object, you're maxed out on installed RAM for your computer, you run Photoshop CS5 as a 64-bit application, and you still need to improve performance, then consider using a solid-state disk as your scratch disk.

 

[roland.g]

No worries. No regrets. Love the performance.

Good to know. Except I thought your SSD was a dud? Really sorry to hear that. Failure rates are fairly low and you tend to hear about more issues here than you would otherwise, but getting a problem machine is never fun. Good luck.

 

[mrfoof82]

Good to know. Except I thought your SSD was a dud? Really sorry to hear that. Failure rates are fairly low and you tend to hear about more issues here than you would otherwise, but getting a problem machine is never fun. Good luck.

Eh, to say I'm used to failing SSDs is an understatement. I deal with entire arrays of them in LUNs in SANs, as well as PCI-E based solutions such as FusionIO. The main issue currently is the implementations of S.M.A.R.T. for SSDs isn't at the predictive level of failure that's been well-established for HDDs, so you have to be more observant since you won't get a blatant bunch of SMART errors being logged. That'll improve over time, thankfully.

It's unfortunate, but aside from the filesystem corruption it's been great. Granted, that *could* just be a firmware issue, but I'm more apt to place my bets on a bum disk instead. It may be until Wednesday that I hear back from Apple on next steps. In the meantime I'm still doing work on it. It's still snappy. I'm just expecting to get a call early next week saying to prep it for return, and having to perform a disk-based backup beforehand.

 

[supersid]

So, your apps open at SSD speed and your media opens at HDD speed? That sounds like it defeats the purpose of having a SSD. What's the point if having a photo app open at SSD speed, if the content of that app opens at HDD speed? Sounds like a waste of money until the SSD drives become larger and more affordable.

Am I wrong or missing something?

I am doing something similar, but I chose to leave my pictures and movies on the SSD for fast access and editing. But for instance my music and DVD rips are on my HDD. Playing music or a DVD does not need the speed of an SSD. Same counts for a lot of document types.

To my opinion you are not missing the whole thing just a part of it.