Why don't Safari give away used memory?

[johannnn]

I'm running a 11" with 2 GB ram so I'm a little careful with the ram.

When opening 10-15 tabs in Safari, the activity monitor says its using ~500 mb ram. However, when I close the tabs, it still uses the 500 mb ram. After opening some new tabs, and then closing them, this number gets even higher.

I guess the consequence is that my 2 GB ram runs out faster because of this and it has to borrow memory from the disc. This has made me look at Chrome where every tab has its own process, and when I close each tab its memory is free again.

Have I understood this memory management correctly? And why isn't Safari freeing its used memory as its not needed anymore by Safari?

Thanks

 

[dissolve]

I think you have it pretty much figured out. Safari doesn't allocate RAM and processing power to each tab, it does so for the entire application. Because of this, it's going to hog a lot of RAM until you actually quit the application. Sometimes, I its behavior looks a lot like a memory leak, but I can't confirm that. Unless you're experiencing slow downs, try not to worry about it too much. You're going to get a lot of page outs with 2GB of RAM, but if browsing Safari is all you are doing, it's not going to have a huge effect. OS X is pretty RAM hungry in general, but it tends to do a good job managing it without notice to the user.

Side note: this is why it's frustrating that Apple kept with only 2GB in the new Airs as a base option. 2GB doesn't go as far as it used to