I'm a designer using Snow Leopard on a MacBook Pro 15" (i7) with 8GB Ram, 500GB (180GB free) (2010 model).
I usually use Chrome (4/5 tabs), Firefox (1/2 tabs), Skype, VM Ware Fusion (with Win XP, using only 512MB), Photoshop CS5, Adium, iTunes, maybe Filezilla.
Photoshop is the main Ram user. It can eat up to 3GB or more as time rolls by, and I'm not working with very big files, 50mb max, and only 2 or 3 open.
When I start opening programs everything works fine. It's later on that you see that you have very (and I mean veryy) little Free Ram left. Between 8MB and 15MB. At the same time I have 2.21 GB of Inactive Memory.
The machine gets much slower once you get below 150MB of Free Memory, and it's a total lie that Inactive Memory gets released onto other programs to overcome this slowness. It never gets released until you close the program.
I wanted to post a screenshot of my Activity Monitor but your site doesn't allow it if I'm a new user.
Once your Free memory gets to these levels (15MB), the Page Outs start increasing and the Inactive Memory never gets released. It gets laggy.
Please don't tell me that a 2010 Macbook Pro with 8GB is not enough to work with Photoshop on small to medium sized files. Normal users (internet, skype, movie watching, etc.) won't have this problem, but if used for design or more heavy tasks (which I believe is this machine's main purpose), it doesn't work properly.
I think this is a very important issue that has never been addressed. I don't know if Mountain Lion has solved this, but I've searched around and haven't read good comments (they even say it eats up more Ram).
Do you know if a MacBook Air i5/i7 8GB 256GB SSD will improve on this matter? Do SSD's improve Ram usage? I'm planning on changing the MacBook Pro (not because of this, because of it's size).
Here's the complete Terminal response from the command top -o rsize -l 1 -S -n 10:
Processes: 92 total, 3 running, 1 stuck, 88 sleeping, 515 threads
2013/03/08 17:33:05
Load Avg: 0.24, 0.28, 0.28
CPU usage: 5.55% user, 27.77% sys, 66.66% idle
SharedLibs: 5796K resident, 4760K data, 0B linkedit.
MemRegions: 22354 total, 4549M resident, 42M private, 1359M shared.
PhysMem: 1322M wired, 4587M active, 1908M inactive, 7817M used, 372M free.
VM: 183G vsize, 1041M framework vsize, 558408(0) pageins, 418(0) pageouts.
Swap: 34M + 222M free.
Purgeable: 81M 183(0) pages purged.
Networks: packets: 235338/116M in, 224406/115M out.
Disks: 135805/3530M read, 131663/2361M written.
PID COMMAND %CPU TIME #TH #WQ #PORTS #MREGS RPRVT RSHRD RSIZE VPRVT VSIZE PGRP PPID STATE UID FAULTS COW MSGSENT MSGRECV SYSBSD SYSMACH CSW PAGEINS USER
296 Adobe Photoshop 0.0 15:12.94 17 1 447+ 1754+ 3349M+ 263M+ 3547M+ 3612M+ 6934M+ 296 144 sleeping 502 1119232+ 8721+ 56249389+ 27765125+ 2528538+ 61681638+ 3147104+ 29186+ owner
341 vmware-vmx 0.0 12:24.49 23 1 216+ 402+ 19M+ 629M+ 711M+ 60M+ 3509M+ 341 1 sleeping 0 479594+ 724+ 373320+ 92479+ 17797849+ 296216+ 10285249+ 166343+ root
0- kernel_task 0.0 10:08.35 73/4 0 2+ 1023+ 76M+ 0B 368M+ 128M+ 3144M+ 0 0 running 0 37759+ 0 78790277+ 73869135+ 0 0 17309424+ 0 root
254 firefox 0.0 04:08.53 29 1 255+ 4957+ 204M+ 238M+ 321M+ 303M+ 4025M+ 250 1 sleeping 502 1399145+ 67635+ 6542552+ 3242741+ 720602+ 7063491+ 537809+ 7020+ owner
276- Skype 0.0 15:06.50 33 2 602+ 932+ 99M+ 110M+ 159M+ 166M+ 1163M+ 276 144 sleeping 502 23219202+ 5402+ 7363050+ 3682250+ 1338611+ 8832162+ 1493925+ 6289+ owner
236- Google Chrome 0.0 04:30.67 31 1 363+ 483+ 109M+ 114M+ 145M+ 323M+ 1353M+ 236 144 sleeping 502 937175+ 29790+ 6074380+ 2834369+ 3647085+ 7080110+ 1273550+ 45988+ owner
66 WindowServer 0.0 07:55.98 7/1 1 440+ 1405+ 15M+ 195M+ 136M+ 76M+ 3197M+ 66 1 running 88 12073018+ 4795+ 3927394+ 1339534+ 3060626+ 5647891+ 2244590+ 2527+ _windowserver
417- Google Chrome He 0.0 00:24.08 5 1 97+ 385+ 83M+ 85M+ 132M+ 164M+ 1169M+ 236 236 sleeping 502 91462+ 1381+ 181063+ 92181+ 155361+ 211895+ 43893+ 13933+ owner
280- Google Chrome He 0.0 01:05.81 9 2 103+ 380+ 97M+ 80M+ 128M+ 190M+ 1173M+ 236 236 sleeping 502 162474+ 1378+ 1519179+ 772658+ 557874+ 1822614+ 241725+ 33033+ owner
3425- Dreamweaver 0.0 00:28.24 12 2 193+ 961+ 51M+ 150M+ 110M+ 105M+ 1263M+ 3425 144 sleeping 502 51623+ 2346+ 977727+ 459446+ 142689+ 1400204+ 228438+ 104+ owner
Best Answer
My experience with inactive memory is similar to yours and as soon as free memory approaches zero, performance takes a big dive. An SSD makes a big difference, not because of RAM usage or even because it improves paging speed, but because it makes it very fast to restart a program and release the "extra" memory it's using. I don't use Photoshop and VMware but Firefox, Safari, and Chrome are all memory hungry and don't appear to ever release memory once they grab it so restarting any of them usually is a quick fix.
Memory usage in Chrome is not as obvious as others because Chrome runs as many separate processes so you don't see a single big number for memory usage.