I have a debian system. It has 8GB memory. When I do top it shows 7.9 GB memory used and rest free. I add up the memory usage of all the programs running from top and they hardly sum up to around 50 MB. So, where is rest of the memory being used? Can I have a better detailed info of the memory usage? What is a better way to check the memory usage?
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This is a  about how Unix operating systems report memory usage.   Similar Questions:                    I have production server that is running Debian 6.0.6 Squeeze  #uname -a  Linux debsrv 2.6.32-5-xen-amd64 #1 SMP Sun Sep 23 13:49:30 UTC 2012 x86_64 GNU/Linux   Every day cron executes backup script as root:  #crontab -e  0 5 * * * /root/sites_backup.sh &gt; /dev/null 2&gt;&amp;1   #nano /root/sites_backup.sh  #!/bin/bash str=`date +%Y-%m-%d-%H-%M-%S` tar pzcf /home/backups/sites/mysite-$str.tar.gz /var/sites/mysite/public_html/www mysqldump -u mysite -pmypass mysite | gzip -9 &gt; /home/backups/sites/mysite-$str.sql.gz cd /home/backups/sites/ sha512sum mysite-$str* &gt; /home/backups/sites/mysite-$str.tar.gz.DIGESTS cd ~   Everything works perfectly, but I notice that Munin's memory graph shows increase of cache and buffers after backup.  Then I just download backup files and delete them. After deletion Munin's memory graph returns cache and buffers to the state that was before backup.  Here's Munin graph:  Externally hosted image was a dead link.
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I've been running Ubuntu 17.10 for a good while. Starting yesterday (April 9) the process gnome-software started using large amounts of memory. I don't know if it is related to the update that I took that day.  gnome-software grows to use up to 7G of memory (my system has 8G of RAM.)  This expands into eating up swap and root. My root usually runs at 51% of its total disk space and it went up to 96%. System ground to a halt. Had to power off. Only after some automatic disk cleaning (?) did root return to 51% usage on its own.  This happened twice yesterday and it is starting again today.  After running only 1 hour gnome-software is now using (according to system monitor) virtual mem=5.4G, Resident me=4.7G, memory=4.7G    More info:    This is continuing to happen.  The root disk space is being used in at least the file /var/log/syslog.  Over the last few hours it has grown to 4.9G in size.  I have to manually kill the gnome-software process and delete the log file to keep the computer functional.  When gnome-software starts using memory, the CPU jumps up and down  from 100% to 0%.  This can be seen in the system monitor program in the resources tab. I verified this by stopping the gnome-software process and CPU usage goes to almost nothing.  Telling the process to continue show CPU usage jumping all over again.  This CPU usage doesn't show up in "% CPU" on the process page.  Probably due to the refresh interval?    Even more info:    This is the error that repeats over and over in /var/log/syslog when this is happening. syslog was 1.7G when I caught it this time.  Apr 10 20:27:31 rwkeating-XPS-8300 gnome-software[2485]: g_byte_array_remove_range: assertion 'index_ + length &lt;= array-&gt;len' failed Apr 10 20:27:31 rwkeating-XPS-8300 gnome-software[2485]: Ignoring unexpected response   I verified this by pausing the gnome-software process while doing a tail on syslog and then un-pausing the gnome-software process only to see the error flooding the log.  So it is caught in this loop.  Don't know what it means ... yet.
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On my Amazing 2GB EeePC Surf, I have no more space left!  This is quite normal, and it happens every now and then. Just delete a few large, unneeded files and everything should be good, right?  So I go and find a 2MB file in /tmp, and rm -rf it. Check free space again, and -- still nothing?!  I had to remove about 30MB of files before it registered some free space.  Now, my question is, what's up with this strange behaviour?
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When I open a RAM-intensive app (VirtualBox set at 2GB of RAM), some swap space is generally used, depending on what else I have open at the time.  However, when I quit that last application, the 2GB of RAM is freed up, but the same swap space use remains.  For example, right now, about two hours after having closed VirtualBox, I have 1.6GB free RAM and still 770MB in swap.  How can I tell Ubuntu to stop using that swap and to revert to using the RAM?
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I recently wiped my computer to have 14.10 as my only OS. It has 160 GB of storage. That was a month ago. Now, I keep getting prompts that the storage is almost full. And when I look it says I only have 543 MB free. How is this possible? I haven't torrented any large files. I do have Variety to autodownload wallpapers and not erase though.  Filesystem Size Used Avail Use% Mounted on  /dev/sda1  146G  138G  554M  100%  /  none 4.0K 0 4.0K 0% /sys/fs/cgroup  udev 742M 4.0K 742M 1% /dev  tmpfs 151M 1.1M 150M 1% /run  none 5.0M 4.0K 5.0M 1% /run/lock  none 752M 540K 751M 1% /run/shm  none 100M 80K 100M 1% /run/user –  er –
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I'm running Linux Mint 14 Nadia.  The Linux partition has 10G.  When the system starts, du reports 80% usage.  Then the usage slowly grows until it reaches 100% and the system becomes unusable.  (It can happen on the order of days or weeks).  After the reboot the usage resets to 80%.  The strangest thing of all is that du shows no change.    Here's output of those commands (Windows and external drive partitions are elided):  # --- Just after reboot ---  $ df -h      Filesystem      Size  Used Avail Use% Mounted on /dev/sda1       9.8G  7.3G  2.0G  80% / none            4.0K     0  4.0K   0% /sys/fs/cgroup udev            428M  292K  428M   1% /dev tmpfs            88M  1.3M   87M   2% /run none            5.0M     0  5.0M   0% /run/lock none            437M  288K  437M   1% /run/shm none            100M   12K  100M   1% /run/user  $ sudo du -x   -d1 -h / 186M    /opt 512M    /var 11M /sbin 556K    /root 1.3G    /home 613M    /lib 8.0K    /media 4.6G    /usr 16K /lost+found 111M    /boot 39M /etc 4.0K    /mnt 60K /tmp 9.1M    /bin 4.0K    /srv 7.3G    /            # &lt;-- note this   # --- After some time ---  $ df -h Filesystem      Size  Used Avail Use% Mounted on /dev/sda1       9.8G  9.1G  199M  98% / none            4.0K     0  4.0K   0% /sys/fs/cgroup udev            428M  292K  428M   1% /dev tmpfs            88M  1.3M   87M   2% /run none            5.0M     0  5.0M   0% /run/lock none            437M   27M  411M   7% /run/shm none            100M   28K  100M   1% /run/user  $  sudo du -x   -d1 -h / 186M    /opt 511M    /var 11M /sbin 556K    /root 1.4G    /home 613M    /lib 8.0K    /media 4.6G    /usr 16K /lost+found 111M    /boot 39M /etc 4.0K    /mnt 520K    /tmp 9.1M    /bin 4.0K    /srv 7.3G    /              # &lt;-- note this   (Note: I use hibernation.  After the hibernation, the usage stays the same, and after reboot, it resets to 80%.)  How do I track what eats the space?  I've read .  I'm still in the dark.  How do I find out which program is responsible for this behavior?  After edit: found it.  The space is claimed by the kernel log, which is seen by dmesg.  It fills up because my machine generates errors at the rate 5 a second.  (It's related to .)  Let the future readers with a similar problem - slowly-filling disk space unseen by du - not forget to try dmesg in searching for the cause.
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I have 8GB of memory on a 64 bit windows 8.1 machine, and windows is telling me I'm using 91% of my memory, yet its simultaneously telling me I'm only using 3GB.  I literally just restarted my machine a few minutes ago because it was being incredibly rediculously slow. I'm currently only running chrome (with a ton of tabs, but doesn't add up to anywhere near 7.5GB). What could be going on here?   Here's a bunch of my current info       I took a look at this:  but I wasn's able to use xperf and the rest didn't lead me to a solution.  UPDATE - RamMap:   UPDATE 2: I checked Resource Monitor at Wouter's suggestion and found an "Image" called lxdecoms.exe with over 6GB of Commt (KB). I tried killing the process, but while it lowered my Commit Charge, it didn't affect "Used Physical Memory". So I restarted hoping to capture it again in full, but its not back yet and yet the problem persists.  I should note that I do have a Centos virtual box virtual machine running on my machine, not sure if that has any weird memory impacts that aren't reflected in the numbers in these tools.   I got xperf working, so here's my resource monitor and a wpa analysis of my xperf output (from xperf -on ReferenceSet -BufferSize 1024 -MaxFile 512 -FileMode Circular  &amp;&amp; timeout 5 &amp;&amp; xperf -d MemUsage.etl):     What is N/A that's taking up 2.7GB of memory? My VM?
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Task Manager shows my total memory usage at 90% of my 6 GB total, but no single process is using more than 250 MB RAM, and the sum of RAM use of all running processes is less than 2 GB. I've tried:   Looking at the numbers in the "Memory" column on the "Processes" tab of Windows 8 Task Manager. Looking at the "Working Set", "Private Working Set", "Shared Working Set", and "Commit Size" columns on the "Details" tab of Task Manager. Looking at similar memory-related columns in Process Explorer. I've tried running Sysinternals RAMMap, but while I'm having the low-memory crisis, it crashes at launch. Once I resolve the problem, RAMMap runs normally, but at that point it's too late.   All show a pretty small amount of memory being used.  There are lots of people asking variants of this question, with various versions of windows, all over the Internet. Some of them manage to solve their low-memory problems, often by re-installing software; sometimes by re-installing windows from scratch. I'm looking for an answer to the general questions that these all share, and that never seem to get answered elsewhere:   Why is total used memory much higher than the memory used by all listed processes, no matter how I try to count them? How could windows "know" that memory is used without knowing what program is using it? What processes might possibly use up memory but not show up on the list? Is there any software out there that can give more information about used memory?   Details specific to my own problem: Since upgrading to Windows 8.1, The problem occurs as soon as I log in. I run out of memory as soon as I ran any program. I noticed in Process Explorer that several instances of iexplore.exe were running, apparently started automatically. One particular instance was only using a few MB of RAM, but showed hundreds of millions of page faults. On a whim, I killed that specific process, and memory usage immediately dropped by 70%.  Leading to one specific question:   How could killing one process that supposedly only used a few MB free up several GB?   And a (presumably hard) bonus question:   Short of re-installing Windows, how might I avoid having to go through this every time I reboot my computer?
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I have a LAMP server with following configuration.  CPU : Intel(R) Xeon(R) CPU   RAM : 32 GB  HDD : 80 GB  Running on virtual environment.  All the things in the server are running smoothly. But I have noticed that the RAM usage is the server is increasing each day without any reason.   This is the current memory usage on my server.  # free -g              total       used       free     shared    buffers     cached Mem:            31         13         17          0          0         10 -/+ buffers/cache:          1         29 Swap:            2          0          2   And you can see the last 8 weeks memory usage below.   And i have executed the following command to find how much memory each process is consuming.  # ps -eo size,pid,user,command --sort -size | awk '{ hr=$1/1024 ; printf("%13.2f Mb ",hr) } { for ( x=4 ; x&lt;=NF ; x++ ) { printf("%s ",$x) } print "" }'          0.00 Mb COMMAND        2253.62 Mb /usr/libexec/mysqld --basedir=/usr --datadir=/var/lib/mysql --user=mysql --pid-file=/var/run/mysqld/mysqld.pid --skip-external-locking --socket=/var/lib/mysql/mysql.sock        1171.66 Mb java -jar /etc/vmagent/bin/VMAgent.jar         138.27 Mb /sbin/audispd         127.75 Mb /usr/sbin/named -u named -c /etc/named.conf -u named -t /var/named/run-root          74.29 Mb auditd          73.03 Mb automount          43.14 Mb /usr/bin/spamd --username=popuser --daemonize --nouser-config --helper-home-dir=/var/qmail --max-children 5 --create-prefs --virtual-config-dir=/var/qmail/mailnames/%d/%l/.spamassassin --pidfile=/var/run/spamd/spamd_full.pid --socketpath=/tmp/spamd_full.sock          43.14 Mb spamd child          43.14 Mb spamd child          37.13 Mb /usr/sbin/httpd          37.02 Mb /usr/sbin/httpd          36.52 Mb /usr/sbin/httpd          36.46 Mb /usr/sbin/httpd          36.23 Mb /usr/sbin/httpd ................   For troubleshooting , i have restarted the MySQL and APACHE servers. But the result was same. Restarting the entire server will fix the issue, but i want to know what is the real issue.  Let me know if you have any idea about this issue.  Thanks,  Arun S
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In my Windows 8, video card shows 640 MB of available memory (Screen Resolution > Advanced Settings or with dxdiag). But ubuntu (with lspci command) shows 256 MB. so who's right?
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When we want to setup a linux system, there is a common a suggestion to set the swap space  twice as big as your physical memory. I want to know why do we need this, and how it is this suggestion come to be?
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I'm looking for a linux alternative to . I would like to know what is taking up space on my hard drives.  A program that works on console and doesn't require a UI is preferred .
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My PC has 8 Gb of ram. Is there any way to make ubuntu use most of it? I mean rarely drop caches and keep once opened programms in ram longer, preload apps on boot, etc.
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Is there a way to quickly check the amount of free / used disk space in Ubuntu?  I would assume you could right click on 'file system' in the file browser and choose 'properties' or something but there is no such option.
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More of a curiosity than a problem;  and, I admit, something of an embarassingly basic question:  I've noticed that on many occasions, on my Linux machine I will have ~500MB of swap space in use, even though I have ~600MB of unused RAM.  My naive high-level understanding was, swap space doesn't kick in until RAM is exhausted.  I went further and made the assumption that this situation must be the doing of the Linux kernel, because a user process that requests memory, does so only logically, and has no notion of whether that memory is physically backed by RAM or the swap space.  Which leads to the question, why would the kernel preemptively use the swap space?  Is this part of some performance tuning algorithm?  Is it swapping out to disk parts of memory that it deems least likely to be accessed (an LRU scheme, perhaps)?  If so, wouldn't it just make sense to leave everything in RAM, and only when nearing exhaustion, then and only then swap the LRU portions from RAM to the swap space?   I should clarify, my linux server has 2GB of RAM and 2GB of swap space.
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Why does my server show              total      used      free   shared buffers    cached     Mem: 12286456  11715372    571084        0   81912   6545228 -/+ buffers/cache:  5088232   7198224    Swap: 24571408     54528  24516880   I have no idea on calculating the memory in linux. I think it says that 5088232 is used where as 7198224 is free, meaning it is actually consuming 5GB of RAM?
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I'm currently building a Java app that could end up being run on many different platforms, but primarily variants of Solaris, Linux and Windows.  Has anyone been able to successfully extract information such as the current disk space used, CPU utilisation and memory used in the underlying OS? What about just what the Java app itself is consuming?  Preferrably I'd like to get this information without using JNI.