I don't even know where to start with the author's complaints about the memory model. Inactive memory is not "memory from a recently used app". Inactive is just like active memory. It is not unused memory. Inactive memory is memory that has not been accessed recently and will therefore be swapped to disk first. Just like active memory, it can be be freed immediately if it has not been modified (eg. a memory mapped file, or a local copy of some shared memory), but if it has been modified, it must be paged to disk because otherwise data would be lost.
All the purge command and "Repair permissions" do is swap out lot's of memory. But this is not unused memory. This memory will likely be paged in again sooner or later. It does not help much if you simply have too little memory. That's why the author claims he has to run the commands again and again. But the problem is not the broken memory management system. The author simply has too little RAM.
Which leaves the question: Why does Mac OS need more RAM than Linux?
Well, there's the simple fact that there is much more stuff running in the background on Mac OS. You have automatic indexing of every file on your hard drive and file system monitoring. Try downloading an app that opens some file type. The moment it is unzipped, the Finder automatically uses it to open supported files.
Then you have an automatic version control and backup system running in the background, for every single file on your hard disk (Time Machine). Additionally, many Mac apps aggressively cache data in memory. Take iTunes. You can scroll lag-free through music libraries with tens of thousands of songs and their album artwork, and filter them instantly.
These things use up RAM. Lot's of it. And that's why you can't run 3 VMs on your Mac if you only have 4GB.
If you don't want the extra features / bloat of Mac OS please go ahead and use Linux. But don't write a completely ignorant piece about how you think the memory management model in Mac OS is broken without reading the real docs: https://developer.apple.com/library/mac/documentation/Perfor...
All the purge command and "Repair permissions" do is swap out lot's of memory. But this is not unused memory. This memory will likely be paged in again sooner or later. It does not help much if you simply have too little memory. That's why the author claims he has to run the commands again and again. But the problem is not the broken memory management system. The author simply has too little RAM.
Which leaves the question: Why does Mac OS need more RAM than Linux?
Well, there's the simple fact that there is much more stuff running in the background on Mac OS. You have automatic indexing of every file on your hard drive and file system monitoring. Try downloading an app that opens some file type. The moment it is unzipped, the Finder automatically uses it to open supported files.
Then you have an automatic version control and backup system running in the background, for every single file on your hard disk (Time Machine). Additionally, many Mac apps aggressively cache data in memory. Take iTunes. You can scroll lag-free through music libraries with tens of thousands of songs and their album artwork, and filter them instantly.
These things use up RAM. Lot's of it. And that's why you can't run 3 VMs on your Mac if you only have 4GB.
If you don't want the extra features / bloat of Mac OS please go ahead and use Linux. But don't write a completely ignorant piece about how you think the memory management model in Mac OS is broken without reading the real docs: https://developer.apple.com/library/mac/documentation/Perfor...