Max out MAC Pro

[alsharp]

Lately I've been doing gigapans (final image size 2Gb to 15 Gb) and am considering Maxing out my mac pro. current processor is 2 X 2.4 quad Core Intel Xeon with 26 GB 1066 DDR3. things work fine in "Stitch" the prietary
stitching software from the Gigapan folks but when I process in Photoshop its slower than 1995. Photoshop CS5 running in 64bit allocated 80% of total ram.
anyway: would it be worthwhile ( more efficient, faster processing time) to add more ( like 2x) ram? Intuitively it would seem that the more ram the faster the image is done but is there a limit to what benefits these large amounts of ram can produce.

 

[nanofrog]

Have you considered that your storage system may be the bottleneck?

 

[Neodym]

Try to check how much storage is used for temporary data (i.e. look at page-out swaps etc.). I'm no expert in that field, but seem to vaguely remember that Ram as rule of thumb should be 2-3x the size of the finished image size when dealing with pictures (any expert reading this please correct me if i'm wrong).

Maybe the Stitch people can tell you more about the temporary amount of memory required or recommended.

 

[Digital Skunk]

Have you considered that your storage system may be the bottleneck?

Agreed, with that much information PS is definitely going to be using scratch disk space to store information. Look into adding an SSD or a raptor (if the SSD isn't to your liking) to your rig and setting it to be your scratch disk.

 

[minifridge1138]

Where can I set the scratch space?

 

[nanofrog]

Agreed, with that much information PS is definitely going to be using scratch disk space to store information. Look into adding an SSD or a raptor (if the SSD isn't to your liking) to your rig and setting it to be your scratch disk.

I expect so.

As I understand it, even if there's more than enough memory, Photoshop still searches for a scratch volume.

Worse yet, other members have discovered that Photoshop is only single threaded in it's write operations with output data. For example, users have tried with hardware RAID systems that can write data at rates of 600MB/s+, and still only see ~250 - 275MB/s for Photoshop.

Gotta love spaghetti legacy code.

 

[nastymrx]

Where can I set the scratch space?

Photoshop preferences.

 

[VanneDC]

hang on.. from everything that ive read and have been told, its not good to use SSD as a scratch disk... due to the frequent writes...

ive located my scratch disk off my SSD just for that reason...

 

[Digital Skunk]

hang on.. from everything that ive read and have been told, its not good to use SSD as a scratch disk... due to the frequent writes...

ive located my scratch disk off my SSD just for that reason...

That may be the case, I've never heard of it, but that's not to say that it isn't true.

If an SSD isn't optimal, then it'll have to be SAS or a Western Digital Velociraptors RAIDed.

 

[Loa]

Hello,

hang on.. from everything that ive read and have been told, its not good to use SSD as a scratch disk... due to the frequent writes...

Two things to consider: most of the info ppl spread around come from 1st and 2nd generation SSDs. Also, even for these "early" SSDs, the write problem has been blown way out of proportion. Add to that the fact that recent SSDs handle this "issue" a lot more intelligently, by levelling the wear across the entire SSD. I can't find the page, but the guys at Anandtech posted something about the real-world durability of SSDs: final word was essentially don't worry about it.

If you're using recent SSDs and really need scratch speed, then by all means go for it.

Loa

 

[nanofrog]

hang on.. from everything that ive read and have been told, its not good to use SSD as a scratch disk... due to the frequent writes...

ive located my scratch disk off my SSD just for that reason...

It depends on the specifics, as the information provided by drive vendors isn't based on real world conditions (particularly how much unused capacity remains, as wear on those cells is increased as the drive is filled with non-temporary data).

That said, there's an easy solution if you use a lot of scratch writes and your current SSD is near full (ideally, you want to keep ~20% unused, including any "reserve"/provisioning capacity not available to the user). Just get a small, cheap SSD solely for scratch (such as the 30GB or 40GB 3Gb/s models from OWC; both are under $100).

If you don't have an available SATA port, there are inexpensive SATA cards that can be used, such as the Highpoint RR620/622 (internal, external respectively).

That may be the case, I've never heard of it, but that's not to say that it isn't true.

If an SSD isn't optimal, then it'll have to be SAS or a Western Digital Velociraptors RAIDed.

Most users won't see this. Most failures under consumer or workstation use would be due to defective units (i.e. controllers die), not damaged cells due to reaching their write cycle limit.

Enterprise use OTOH... (think SAN used for a relational database). That crazy number of years provided by vendors can be reduced to 3 - 5 under the such conditions, and that's using SLC based drives.

Two things to consider: most of the info ppl spread around come from 1st and 2nd generation SSDs. Also, even for these "early" SSDs, the write problem has been blown way out of proportion. Add to that the fact that recent SSDs handle this "issue" a lot more intelligently, by leveling the wear across the entire SSD. I can't find the page, but the guys at Anandtech posted something about the real-world durability of SSDs: final word was essentially don't worry about it.

Consumer users don't really need to worry, so long as they don't fill the drives completely (keep ~ 20% unused, based on the total capacity = user accessible + any provisioning).