When are 6 cores better than 4 cores for home, non-pro use?

[Cheapassmac]

I've never seen preview take so much memory before, thanks for sharing. Memory used when Preview is high is in the 14gb, which is in striking range of going over. Pressure is going to stay green unless you're constantly moving data. I don't think just loading them once will change the pressure.

How big are these complicated PDFs, and are you opening and closing them all up in rapid succession?

 

[F-Train]

You don't need to be a pro user to benefit from the extra RAM. Check out activity monitor and see in the memory tab how your memory pressure is during max usage (with all your daily apps open and as many browser tabs you typically keep up). If yellow/red, have a noticeable amount of swap used, or very small amount of cached files, then it will certainly help.

From my experience, almost everyone will get a boost from 16GB RAM over 8GB. However, very few people would benefit from the 16 to 32GB bump (and the people who actually need the 32GB, would actually benefit more with 64GB).

I've had 32GB of RAM in its packaging for two weeks. Know why I haven't installed it yet? Because on 8GB my world isn't ending

 

[tpivette89]

I just upgraded mine from 8 to 16. Prior to the upgrade, Activity Monitor reported usage in the 5 - 6.5 GB range (always green). Afterwards, usage has jumped up to around 10GB... so I guess it's true that Mac OS will utilize whatever it has available. Although, now, my ceiling has jumped from 1.5GB to 6GB.

I will say that my Geekbench scores improved slightly after the RAM upgrade.

 

[Cheapassmac]

I've had 32GB of RAM in its packaging for two weeks. Know why I haven't installed it yet? Because on 8GB my world isn't ending

Are you sure it's not because you're too lazy/unmotivated to do it

8gb is certainly passable and not crippling for most use. I'm sure you'd be able to appreciate the jump (though I wonder whether you would have been benefitted just as much with a 16gb upgrade kit instead).

 

[F-Train]

Are you sure it's not because you're too lazy/unmotivated to do it

8gb is certainly passable and not crippling for most use. I'm sure you'd be able to appreciate the jump (though I wonder whether you would have been benefitted just as much with a 16gb upgrade kit instead).

For me, it was either pay Apple US$200 for 16GB or pay $300 for 32GB and install it myself. For the price difference, I went with the latter.

I'm finding that the computer is pretty capable with 8GB and the internal graphics. I've been running some Final Cut 4K tests to figure out where my external video card improves over the internal card. On exports, it's a clear winner. On rendering, I'm having trouble identifying clear cases where the internal card isn't up to the task. I think that this may be a reflection of how well Final Cut is integrated with Mac OS.

I've done most of the tests that I want to do on 8GB/internal graphics (Final Cut, Lightroom, Logic, etc) and will redo them once 32GB of RAM is loaded, just to see where more RAM makes a difference.

 

[ixxx69]

I just upgraded mine from 8 to 16. Prior to the upgrade, Activity Monitor reported usage in the 5 - 6.5 GB range (always green). Afterwards, usage has jumped up to around 10GB... so I guess it's true that Mac OS will utilize whatever it has available. Although, now, my ceiling has jumped from 1.5GB to 6GB.

As long as you keep opening stuff, cache will keep increasing. When Memory Used approached Physical Memory (RAM), then the OS will start dumping the cache.

"Memory Used" includes the Cached Files, so when estimating how much RAM is "available", you should really subtract the cache.

If you look at @Spectrum 's memory usage screenshots (post #200), you'll see that it started with 4+GB of cache, but as the memory usage approached the RAM limit, cache gets flushed down to ~1.5GB.

Specrum's swap does go up a couple GB during his testing. That indicates for absolute optimal performance, the computer would benefit from more RAM if that was typical usage. However, under that kind of usage, you're probably not going to perceive any slowdowns unless you're really sensitive to an extra second here or there.

This is where that crazy fast SSD comes in - Apple isn't just including that for bragging rights - it's a major component of overall optimal system performance. For non RAM-intensive usage, unless you're very sensitive, you probably won't perceive a few gigabytes of swap here and there. Where you would mostly notice performance degradation due to lack of RAM is where a lot of memory is being manipulated very quickly, e.g. video editing, encoding/rendering, heavy use of photoshop effects on huge images, GPU, etc.

Something like opening and closing PDF's is very static memory usage. Even if the OS has to flush the cache and write a GB PDF to swap and load another GB PDF into RAM, that can happen faster than most people would notice.

I would suggest everyone who's posting on this stuff (or just curious) to read the Apple page on "How to use Activity Monitor on your Mac" if you're not already familiar with how to comprehend RAM usage.

 

[Spectrum]

Thanks for the link! What still doesn't make sense to me is why writes to the swap don't constitute red activity, and how the swap amount can reduce. I am sure this was always increasing in prior OS versions.
FWIW, the PDF file is 260MB with complex line art and this was on a 16 GB i7 iMac. I was opening it and then scrolling around. It is multiple pages, but Preview will only render about 4 pages at a time, then they get flushed and it has to rerender (or reload?) Will test again the Mac mini (8GB RAM).
Are you suggesting that for this task I'll not see performance improvements? Currently I get beach balls, which I assumed happens whenever RAM is starved. Is that not true?

 

[ixxx69]

Are you suggesting that for this task I'll not see performance improvements? Currently I get beach balls, which I assumed happens whenever RAM is starved. Is that not true?

You still might. There are a number of factors that could contribute depending on what other software is currently using resources as well as the way Preview itself works.

The first obvious check on this is to see if it happens when you have plenty of memory available.

I would also have the activity monitor visible while you're testing the PDF... besides memory usage, check CPU usage... is Preview pegged at 100% when it beachballs? Are there any other apps running with high CPU utilization when it beachballs?

I'm not suggesting you wouldn't benefit from more RAM if your usage regularly maxes out the RAM, only that certain usages will benefit more noticeably from more RAM when memory pressure becomes an issue.