I remember, back from my days with Windows Vista/7, that there was a tool called memclear or memclean that would free some memory by invoking the NT garbage collection API. Probably it cleared cache too. Very often when I use Ubuntu, after a while the system stays at a couple of gigabytes allocated memory, and when I perform memory-intensive tasks such as image editing, I have to wait quite a while for the extra gigabytes to swap.  Is there a way to force something like a kernel GC to free memory that really isn't used? (when I start up, memory consumption is less than a gigabyte)
5619
Prior to doing some benchmarking work how would one free up the memory (RAM) that the Linux Kernel is consuming for its buffers and cache?    Note that this is mostly useful for benchmarking. Emptying the buffers and cache reduces performance! If you're here because you thought that freeing buffers and cache was a positive thing, go and read . The short story: free memory is unused memory is wasted memory.
71145
Well well well...my computer keeps on eating whatever free space is available in the hard drive. It doesn't care whether the free space is in kb,KB,MB or GB. It happens only in the C drive where my OS &amp; other program files are installed.  I used a software Windir Stat or something like that (I don't remember the name exactly) to analyze the usage of space by various programs.  In my C drive, there's a folder named AppData with loads of useless files. I don't know whether they are useful or not? Are they useful?  I was thinking about deleting the contents of that folder. I visited  for more info. WHich folder should I delete???
37116
Within the output of top, there are two fields, marked "buff/cache" and "avail Mem" in the memory and swap usage lines:    What do these two fields mean?  I've tried Googling them, but the results only bring up generic articles on top, and they don't explain what these fields signify.
47013
I am trying to find out how much memory my application is consuming from within the program itself. The memory usage I am looking for is the number reported in the "Mem Usage" column on the Processes tab of Windows Task Manager.
65415
I have 4GB RAM. When I open Firefox, IntelliJ IDEA or VS Code and some other application my memory is about used up thus my machine hangs and I can't do anything. I can't even close any applications.    Date and time are shown in the top bar so that I can view it any time without any thing typing.   If I would view memory status in this way without typing anything then I can make a decision whether to open an application or whether this application may put my machine in hanging state or not.    Is it possible in Ubuntu 18.04 LTS?
42246
I have been having an issue where, if my system is up for a few days without being rebooted I will start getting warnings saying "Close programs to prevent information loss" and then a dialogue suggesting I close programs, which I can either cancel or hit "close programs" and Windows will force close some or all of the applications listed in the dialog.  I open task manager, and see that only around 30% of my memory is currently being used:    When I open resource monitor to see how much committed memory is being used by specific applications, I still see relatively low memory usage:    I've had this problem for awhile and have struggled to find a solution. I've investigated causes like a driver leak by using poolmon, but never saw anything in poolmon that matched what others have described as red flags for a driver memory leak. What makes me particularly confused is why Win10 is telling me to close applications when I only have 33% of system memory being used.
80217
I am using Windows 7 64 bit with 8G ram. After some use, I feel Windows is getting sluggish. The drive is thrashing. When I look at the resource monitor and disk activity, I see a few instances of use of the page file (c:\pagefile.sys). I check the physical memory and I see about 2.3G available memory and 700M free memroy.   Why doesn't Windows use more of the free memory and less of the page file? Does it need to leave some x amount of free ram, how much would that be? Is it a percentage of physical ram?  My plan is get more ram and an SSD for the main drive. Meanwhile I am suffering from slow performance.
122640
I'm having a problem with my ram on windows 7. The ram is clearing or programs are using and dumping it faster than it can clear. I have 8gb of ram I'm only using 4gb and the rest is in Standby. At best time I can get 100mb of free but its mostly at 15mb or less. I suspect a memory leak but I have no way to figure out what program it is. I have not installed any new hardware recently and newly installed programs have bin closed. Does any one have an idea of what is going on and how to fix it?   I'm sorry this is so little information but that is all I have as well.  Edit: I tried RamMap and found out the my "Mapped File" has 3,291,784k ram in standby how do I figure out what program and how do I limit it's ability to set ram in standby?  Edit: I keep getting a problem when I will have 0 free ram and my computer will stop working properly. It will become outrageously slow where it will take 3-4 minutes to start task manager so I can close some programmes. When I free up some ram by closing some programmes every thing runs normally. It does not matter which programs I closes only that I free up some ram. I know a lot of you say it's supposed to be like that and that's how windows works. But its obviously a problem and my computer has never worked that way neither has any of my other computers. I would like to fix this please help me.
18053
What is the difference between new/delete and malloc/free?  Related (duplicate?):
63573
I was using my MacBook Pro (with 16GB of RAM) as usual and out of blue I've this popup that:  Your system has run out of application memory. To avoid problems with your computer, quit any applications you are not using.   I've obviously closed few which I could, but it didn't help. After checking on memory, it seems kernel task ate 7GB and 22.36GB swap memory was used of total 23GB (which obviously was the case). However I've still 20GB of space free on my SDD.  Activity Monitor didn't help much whilst my OS X was heading to the destruction.    My top stats before my kernel freeze: Processes: 344 total, 2 running, 5 stuck, 337 sleeping, 2580 threads                                                                                                                         19:23:56 Load Avg: 1.56, 1.62, 2.09  CPU usage: 3.51% user, 8.47% sys, 88.1% idle   SharedLibs: 46M resident, 0B data, 6572K linkedit. MemRegions: 757970 total, 2139M resident, 56M private, 907M shared. PhysMem: 9410M used (6198M wired), 556M unused. VM: 1155G vsize, 1311M framework vsize, 112872658(320) swapins, 122668389(0) swapouts. Networks: packets: 299419263/363G in, 142126838/14G out. Disks: 58970173/1079G read, 20012389/1120G written.  At the end my OS X frozen and I had to do hard reset, repair my SDD in recovery mode and fixing afterwards (recovering lost work, fixing application conflicts, checking my lost+found folder, Chrome/Terminal tabs gone, headache, etc.). My question is, how do I check on high memory usage of kernel task or how to properly deal with that kind of situation? I've tried to take Sample with Activity Monitor, but it's greyed out.  My MacBook Pro details: 2.3GHz Intel Core i7 (late 2013) with 16GB RAM. OS X: 10.9.5
59383
Is Kernel space used when Kernel is executing on the behalf of the user program i.e. System Call? Or is it the address space for all the Kernel threads (for example scheduler)?  If it is the first one, than does it mean that normal user program cannot have more than 3GB of memory (if the division is 3GB + 1GB)? Also, in that case how can kernel use High Memory, because to what virtual memory address will the pages from high memory be mapped to, as 1GB of kernel space will be logically mapped?
19077
I developed an algorithm for a fairly hard problem in mathematics which is likely to need several months to finish. As I have limited resources only, I started this on my Ubuntu 12.04 (x86) laptop. Now I want to install some updates and actually restart the laptop (the "please reboot" message is just annoying).  Is there a way to save an entire process including its allocated memory for continuation beyond a reboot?  Here is some information about the process you might need. Please feel free to ask for further information if needed.   I called the process in a terminal with the command "./binary &gt; ./somefile &amp;" or "time ./binary > ./somefile &amp;", I cannot really remember. It's printing some debug information to std::cerr (not very often). It's currently using roughly 600.0 kiB and even though this will increase, it's unlikely to increase rapidly. the process runs with normal priority the kernel is 3.2.0-26-generic-pae, the cpu is an AMD, the operating system is Ubuntu 12.04 x86. it runs since 9 days and 14 hours (so too long to cancel it ;-) )
84590
I have a notebook here that I suspect has a faulty memory module. I therefore downloaded  and let it run.  Note that the screenshot is not my actual one, it's provided by memtest86+    How do I interpret the numbers on the screen? I've let it run for about four hours and now I'm in pass 7.  Especially, what does   the test number the count of Errors the count of ECC errors   indicate? What are sane values for memory errors? At which point should I consider replacing memory?
66029
I wrote C++ for 10 years. I encountered memory problems, but they could be fixed with a reasonable amount of effort.  For the last couple of years I've been writing C#. I find I still get lots of memory problems. They're difficult to diagnose and fix due to the non-determinancy, and because the C# philosophy is that you shouldn't have to worry about such things when you very definitely do.  One particular problem I find is that I have to explicitly dispose and cleanup everything in code. If I don't, then the memory profilers don't really help because there is so much chaff floating about you can't find a leak within all the data they're trying to show you. I wonder if I've got the wrong idea, or if the tool I've got isn't the best.  What kind of strategies and tools are useful for tackling memory leaks in .NET?
110321
I have my paging file turned off in Vista as i have heard that it is not needed and in some cases may slow down a system that has >=2GB RAM. (no sure how true this is, but i notice that having it switched off doesn't really impact performance noticeably.  I have been reading about Readyboost and it sounds like caching with the benefits of flash memory (low latency etc.)  Which of these would i be better off using?  edit: i have 2gb, and have been using the machine without a pagefile today, and haven't noticed much obvious performance degradation, but will take your suggestions on board. would be good if any claims can be backed up please.
55373
I have an Asus G50vt-x5 laptop with 4GB of RAM installed. But Ubuntu 10.10 shows only 3GB of RAM. Why is it only showing 3GB of RAM instead of the full 4GB? output of free command is :  neal@ubuntu:~$ free              total       used       free     shared    buffers     cached Mem:       3095668    2972784     122884          0     747996    1590044 -/+ buffers/cache:     634744    2460924 Swap:            0          0          0
39763
I have a device that needs a block of memory that is reserved solely for it, without the OS intervening.  Is there any way to tell BIOS or the OS that a block of memory is reserved, and it must not use it?  I am using this device on an openSUSE machine.