Closing the process with top RSS usage might do very little for decreasing memory pressure. One reason is that much of the physical pages can be shared, indeed most of them usually are, on my system a chrome process has a 120MB RSS, but after closer inspection 110MB is shared, and after even closer inspection 90MB is shared with non-chrome processes. The "real memory" column is resident set size, a completely useless metric for the problem at hand because of many reasons. In a virtual memory system with on-demand paging, memory mapped I/O, shared libraries and copy on write pages even measuring and interpreting memory stats is very difficult and subtle. Sorry, but no, you're just illustrating the problem I've mentioned. I read the first paragraph about memory management and decided to give it one more chance, but then repair permissions was mentioned as a solution. Of course, this feature doesn't magically repair anything, but it's sold as a panacea. It's funny how much can one advocate for something when all alternatives are the same.īut all memory management rants are nothing compared to mentioning Mac OS X' repair disk permissions feature. There are various differences in implementation making each system optimized for particular workloads, but understanding the differences between the system is out of reach of most people who complain on their blogs, and it only affect out-of-reach workloads anyway. The way file systems, file system caches, virtual memory, and shared libraries in the context of virtual memory interact is architecturally identical on all major operating systems today, including Windows, Mac OS X, Linux, Solaris, and the BSDs. Everybody talks about things like "this app is using 300MB of RAM", when such statements don't make any sense in the modern world. The users are presented with data they don't understand. Most people, even most technical people, don't know about the implications of shared libraries in memory measurement. It's understandable, most people don't know and don't have to know what virtual memory is, even if they have a superficial understanding of swapping. On virtual memory systems with on-demand paging that use shared libraries and where all file system I/O is mmap(2) based, memory is managed in a very different way than what most people expect. When someone rants about memory usage it is usually a sign he knows nothing what he is talking about.
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