Questions tagged [virtual-memory]

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79
votes
6answers
144k views

What I can delete from /private/var/vm?

What is this folder? It's huge and I can use the extra room. I've read sleepimage isn't necessary—is this true? Should I just deal with it? Is the "private" folder emptied automatically, or would I ...
51
votes
13answers
56k views

Why would I disable swap file in Mac OS X?

I came across a thread about installing an SSD drive in MacBook Pro. Someone in the comments also recommended to disable the swap file but didn't say why: sudo launchctl unload -w /System/Library/...
41
votes
1answer
2k views

How is the Y value for the Memory Pressure graph in Activity Monitor calculated?

How is vm.memory_pressure's value bounded / calculated on OS X 10.10.2 - Yosemite? I've researched several answers to this question and am trying a few things on the command line to get exact values ...
33
votes
3answers
35k views

How can I move virtual memory swap files to a different drive or partition?

note: This is a question that I asked on SuperUser a while ago. I'm re-posting it here because I think it belongs here. By default, Mac OS X stores its swap files in /private/var/vm/. I would like to ...
24
votes
3answers
65k views

What are the “sleepimage” and “swapfile” documents?

I was using Disk Inventory X and found a file called sleepimage in /private/var/vm/ It takes up 4 GB! I also found numerous other files in the same folder called swapfile0 swapfile1, etc. What are ...
21
votes
5answers
16k views

What does it mean if I have lots of “Inactive” memory at the end of a work day?

After a day's of work at my MacBook Pro running Mac OS X 10.6.5, Activity Monitor shows that the majority of my computer's 8 GB of memory is "Inactive", and only a tiny sliver of the pie chart is "...
16
votes
2answers
13k views

vm_compressor_mode (vm.compressor_mode) values for enabled compressed memory in OS X

Background In Super user, with an accepted answer: Disable compressed memory in Mac OS 10.9 Mavericks? Also in Super User: how to get memory compress back in Mac OS 10.9 Mavericks? – and from ...
15
votes
2answers
7k views

What is memory pressure, and how do I relieve it?

I have had my machine for more than a year now, and I'm looking at Memory Pressure in the Activity Monitor. What is this memory pressure and How do I "relieve" this memory pressure from my system? ...
14
votes
4answers
14k views

When will Finder use large amount of memory?

Sometimes I see the iMac with 4GB of RAM having a few MB of swap file only, and after I left for a few hours and come back, the swap file is 2.7GB. Looking into the Activities Monitor, the Finder is ...
12
votes
3answers
18k views

How does memory management work in Mac OS X?

I am a university student who has been trying to write a compare and contrast paper between how Windows, Linux, and Mac OS X manage memory. For instance, with Windows, it's physical memory (RAM) and ...
12
votes
4answers
21k views

Safari is using too much RAM. How can I reduce its memory footprint?

I'm finding Safari (Latest - v5.0.2) to be even more of a memory hog than usual. (Currently using 465mb of RAM with only this tab open, but having been running for a while) Closing it and ...
11
votes
2answers
2k views

How to access /dev/mem in OSX?

How I can access /dev/mem (or /dev/kmem, /dev/pmap) equivalent device in OSX? As far as I know it was removed in some point. Can I create this node manually somehow or any other way of dumping the ...
11
votes
2answers
2k views

vm_compressor=VM_PAGER_DEFAULT in Yosemite caused freeze when physical memory was full

The memory compression caused frequently lag so I tried turning it off by using the command sudo nvram boot-args="vm_compressor=1" The lag was gone but I got crashing freeze when I opened some ...
11
votes
1answer
934 views

Why does Dashlane use so many ports?

I use Dashlane to store passwords, and I like it, but there's one problem I've had with it. I use Activity Monitor to see what's going on, and something strange has been happening with Dashlane lately....
11
votes
1answer
5k views

How to free up a swap space manually without restart?

I'm on High Sierra on MacBook Pro with 16GB of RAM with SSD. Got 15G of swap files, is there any method of freeing swap space/files without restart? $ sysctl -a | grep swap vm.swapusage: total = ...
10
votes
2answers
9k views

Is there a way to reduce the swappiness of OS X 10.6 Snow Leopard?

I have 6GB on my old Macbook, with an SSD. I would like to avoid writing to the swap file as much as possible. Ever since my upgrade, I have always had at least 1 to 1.5GB memory "free". Yet, I ...
9
votes
1answer
3k views

Why does OS X use virtual memory when I still have free RAM?

I have this awesome MacBook Pro with 8 GB of RAM. When I open up Activity Monitor it would seem that I have plenty of RAM available, but my computer seems to prefer to use virtual memory for many ...
9
votes
3answers
3k views

MacBook Running Really Slow, Activity Monitor Reports HUGE VM

My MacBook is running really really slow at the moment, I have quit loads of processes (but activity monitor only reported about 10% cpu usage anyway). I had just noticed I have a VM Size of 250GB! ...
9
votes
2answers
3k views

How can virtual memory be greater than the total available space?

Why does my MBP sometimes report VM Size: 300+ GB in Activity Monitor under System Memory tab, when my hard disk size is only 250 GB (total) and RAM is 4GB? I know it can't magically get that extra ...
8
votes
1answer
5k views

Why is it that my Mac would rather swap than clear inactive memory?

Why is it that my Mac (running 10.8 Mountain Lion) would rather swap than clear inactive memory? I know people say that the Mac OS manages itself and whatever, but there is a serious performance dip ...
8
votes
2answers
1k views

Trouble Understanding Inactive Memory in MacOSX

I thought that I understood how MacOSX manages memory, but recently I’ve become baffled by its performance. Here is the situation: I have a brand new Core i7 system with 8GB of physical memory ...
8
votes
1answer
15k views

Is there a way to limit the size of the disk swap file in Mac OS X?

It seems to be that in OS X, whenever you are out of ram the system happily swaps to disk. This easily becomes an disaster due to the fact that the swapped out memory eventually fills my drive. On my ...
7
votes
2answers
5k views

Disable inactive memory swapping

Background: OSX keeps some information in RAM that is no longer used, but was recently used. This is called inactive memory, and is intended to improve user experience by speeding up some actions: ...
7
votes
3answers
3k views

Tell macOS to only use swap and compressed memory when really needed (macOS 10.14 Mojave)

As disabling swap and/or compressing memory is not recommended and also not a stable option after 10.9 Mavericks (despite the vm setting exists), I'm doomed after few days of running my Mac with my ...
7
votes
2answers
783 views

How can I diagnose really poor performance of my 13" MBP 2011 on 10.6?

The specs are: 2011 MBP 13" Core i7 4Gb RAM 320Gb HDD (not SSD) I use the system for work everyday, I almost always run the following: Mail.app Chrome (7-10 tabs) Terminal (2-3 sessions) Skype ...
7
votes
4answers
25k views

Startup disk has no more space available for application memory?

I purchased a new Macbook Pro (8,3) last April, and have been using it heavily for xcode development, and little else. This morning a message popped up: "Your Mac OS X startup disk has no more space ...
7
votes
1answer
3k views

How can I increase the maximum allowed swap space?

When I try to do a calculation that needs to allocate and use 128 GB of memory (it is a command line program written in C), the kernel kills my process with extreme prejudice. This console log entry ...
6
votes
1answer
7k views

VM size in Activity Monitor: hundreds of GB?

When I open the Activity Monitor, I get something looking like this: http://support.apple.com/kb/HT1342. But why the heck is "VM size" around 100-200 GB?? Here is the capture from the apple support: ...
6
votes
2answers
5k views

what do App Memory, Wired Memory, and Compressed mean?

In Activity monitor, what do App Memory, Wired Memory, and Compressed mean? For example, I am used to the columns in the output of free from procps-ng under Linux. By the way, how can I install ...
6
votes
1answer
246 views

What is the difference between “/private/var/vm” and “/vm”?

I’m wondering why my Mac (running macOS High Sierra 10.13.6) has both /private/var/vm and /vm: $ ls -l /private/var/vm /vm /private/var/vm: total 4194304 -rw------T 1 root wheel 1073741824 May 17 ...
6
votes
3answers
4k views

Is it possible to use a SD card as virtual memory in OS X Server?

I have a 8gb High Performance SD card that I would like to use as swap (virtual memory). Is this possible in Mac OS X Server, and if so how do I go about doing this?
5
votes
8answers
6k views

Mac OS X is not creating a swap file

I recently started running into a lot of memory issues on my mac running High Sierra. Rather than the force quit window coming up, my system would freeze completely and the only way to recover is to ...
5
votes
2answers
1k views

Inspecting kernel_task

I have two MacBooks, one with a fresh OS X install and one with an older install. The older one has a kernel_task taking 1.52 GB of RAM. The newer one—416 MB. These aren't identical machines or ...
5
votes
1answer
489 views

Activity Monitor show no processes

With 10.13. I using Item2 to compile golang (src/all.bash). When cpu is get 100% The Item2 can't response. I have already open Activity Monitor. But I can't force quit the Item2. Then I quit ...
5
votes
1answer
3k views

Minimum virtual memory (swapfile) size setting

Is possible set the minimum swapfile size in OS X? Currently OS X allocating swapfiles on demand, e.g. when when need 3.2GB will allocate 4GB and so on. But when the swap requirements start getting ...
5
votes
1answer
6k views

Mac virtual memory: how to make OS X create swap (page) files as freely with a normal boot as it does with a safe boot (swapfile1 etc)

Background When my MacBookPro5,2 with 8 GB memory boots in safe mode I see that the operating system causes dynamic_pager(8) to create swap files in a way that's relatively unrestrained. In the file ...
5
votes
0answers
2k views

How to increase swap memory in OS X?

I think my swap memory is hitting its fullest and would like to know how to increase it. I very often hit my 8GB RAM limits and my memory pressure (as seen in Active Monitor) goes red quite often. ...
4
votes
4answers
1k views

Does it make sense to Quit apps before Sleep?

Will quitting (Cmd+Q) large apps before closing the MacBook lid make getting up and running again faster? I have the impression that my MacBook needs more time to recover from sleep if I have large, ...
4
votes
1answer
7k views

How do I diagnose my Python program being killed due to an out-of-memory error?

I've been building a Neural Network that analyzes large amounts of data (40G), and my iMac kills the process after it's been running for about a day. In the past, on Linux, I've created a large swap ...
4
votes
1answer
733 views

OS X: Memory usage freaking me out

I know, OS X 10.10 memory management knows what it does, it is good, you shouldn't question it. But this, I do not understand. I have 16 GB of RAM, 6 GB used, plus 2.5 GB app-cache, 1 GB file-cache ...
4
votes
1answer
4k views

What is the OS X equivalent to the free command to show buffer and cache memory?

The free command displays the buffer and cache memory on Linux. What is the command to show the equivalent information for an OS X machine?
4
votes
3answers
2k views

OS X Lion behaving oddly after upgrading to 16GB RAM

Just upgraded Early 2011 Macbook Pro w/ 4GB RAM to 16GB RAM. System now sometimes runs smoothly and other times pauses frequently. Terminal keeps giving me 'System is low on disk space/memory' error....
4
votes
1answer
57 views

KEUbvKya proccess

KEUbvKya process run in my macbook and using 99% cpu and 4gb memory .I Cannot End prccess Plz see the picture
4
votes
1answer
5k views

MacOS uses virtual-memory / swap a lot

I have a MacBook Pro at work and I think it uses too much swap instead of RAM. Model Name: MacBook Pro Model Identifier: MacBookPro13,1 Processor Name: Intel Core i5 Processor Speed: 2 GHz ...
4
votes
1answer
3k views

Any performance gains when disabling secure virtual memory?

To disable secure virtual memory in 10.7, one does the following: sudo defaults write /Library/Preferences/com.apple.virtualMemory DisableEncryptedSwap -boolean yes However, are there any benefits ...
4
votes
2answers
945 views

Why is my memory still inactive after purging?

I'm trying to understand how memory is allocated on my machine. I have read, and believe I understand, these posts and associated links: Trouble Understanding Inactive Memory in MacOSX, Inactive ...
4
votes
2answers
2k views

How to calculate Virtual Memory Size in Mavericks

I would like to know if there is a command (or set of commands) that calculates each of (Virtual Memory, File Cache and App Memory) parameters listed in the screen shot above.
4
votes
1answer
2k views

find what's producing inactive memory

First of all i'd like to ask politely for all of those who feel the need to explain it to me how perfect apple's memory management is to ignore this thread. A little background: The theory goes that ...
4
votes
3answers
1k views

Should I Move The Swap Location For My Mac From The SSD To The Larger HDD In My Laptop?

Should I move the swap location for my Mac from the SSD to the larger HDD in my laptop? Background information: I've heard some suggestions in the general PC/Windows world that if you have an SSD for ...
4
votes
1answer
415 views

In Activity Monitor, how can Swap Used be more than Page Outs?

I am trying to understand the relationship between Page Outs and Swap Used as displayed in Activity Monitor. Currently, Activity Monitor shows: Page outs: 1.6 MB Swap used: 8.1 MB How can there ...