Server :: Like To Understand Linux 'free' Command With Respect To Cache And Free Memory
Mar 27, 2010Was wondering if anyone can explain briefly the relationship of "cache" and free memory in the "free" memory command.
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Software :: Free - Buff - Cache Memory On Debian
Jun 18, 2010What it's the difference between buff(ered) and cache portions of memory?
Code:
Programming :: Free-ing Memory - C/C++ - Free()
Jan 29, 2010Here is the code, which just creates a dynamic array? fills it? and prints.
At the end-point? when doing 'free(digits);' I get a debug messge. But the programm continues to work, or it crashes only on free?
How do I need to change the source-code, not to recieve a message from debugger?
Ubuntu :: Understand The Output From 'free' Cmd?
Sep 20, 2010I don't understand the output from 'free' cmd.
[Code]....
WHy in first line in columns representing 'used', 'free', 'buffers', 'cached' are such values? I can't count them properly.
Server :: Use System Monitor Via A VNC Connection The Free Disk Space Value Is 20GB Free On The Same Volume
May 18, 2011I've got a question on free disk space. I'm currently running CentOS 5.5 on in Xenserver virtual environment. We've had an issue with disk space. My question is as follows: - from a ssh connection i run df -h this gives the value of 90% used leaving me with 9GB. If I use system monitor via a VNC connection the free disk space value is 20GB free on the same volume. Which one is correct? I do use SNMP to monitor the same volume and should alert me when < 10% is free I know this works as I set the alert threshold to < 90% I get an alert.
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Jun 20, 2010Why linux uses swap space, even if there are free physical memory available.
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Dec 10, 2010Nagios had alerted me that the server had a very high load average exceeding the critical level (17+), when logging onto the server I found that all 4GB of the swap was in use despite the fact that there was 15GB+ of free memory (and that's not even including memory from cache and buffers!) Because it seems all heavily used pages were being stored in swap, the I/O wait on the server became very high, and 4 kswapd daemons were taking up nearly 100% available CPU. This did coincide with an error reported by Bacula during a backup job while changing to a bad tape...
From /var/log/bacula.log:
Code:
10-Dec 02:11 bacula-sd JobId 1898: End of medium on Volume "4097" Bytes=434,170,000,000 Blocks=217,084 at 10-Dec-2010 02:11.
10-Dec 02:11 bacula-sd JobId 1898: 3307 Issuing autochanger "unload slot 4097, drive 0" command.
10-Dec 02:12 bacula-sd JobId 1898: 3301 Issuing autochanger "loaded? drive 0" command.
10-Dec 02:12 bacula-sd JobId 1898: 3302 Autochanger "loaded? drive 0", result: nothing loaded.
10-Dec 02:12 bacula-sd JobId 1898: 3304 Issuing autochanger "load slot 4096, drive 0" command.
10-Dec 02:13 bacula-sd JobId 1898: 3305 Autochanger "load slot 4096, drive 0", status is OK.
10-Dec 02:13 bacula-sd JobId 1898: Volume "4096" previously written, moving to end of data.
10-Dec 03:51 bacula-sd JobId 1898: Error: Unable to position to end of data on device "Tape-1" (/dev/IBMtape0n): ERR=dev.c:1384 read e
rror on "Tape-1" (/dev/IBMtape0n). ERR=Input/output error.
10-Dec 03:51 bacula-sd JobId 1898: Marking Volume "4096" in Error in Catalog.
10-Dec 03:51 bacula-sd JobId 1898: 3307 Issuing autochanger "unload slot 4096, drive 0" command.
10-Dec 03:58 bacula-sd JobId 1898: 3301 Issuing autochanger "loaded? drive 0" command.
10-Dec 03:58 bacula-sd JobId 1898: 3302 Autochanger "loaded? drive 0", result: nothing loaded.
10-Dec 03:58 bacula-sd JobId 1898: 3304 Issuing autochanger "load slot 4098, drive 0" command.
10-Dec 03:58 bacula-sd JobId 1898: 3305 Autochanger "load slot 4098, drive 0", status is OK.
10-Dec 03:59 bacula-sd JobId 1898: Wrote label to prelabeled Volume "4098" on device "Tape-1" (/dev/IBMtape0n)
10-Dec 03:59 bacula-sd JobId 1898: New volume "4098" mounted on device "Tape-1" (/dev/IBMtape0n) at 10-Dec-2010 03:59.
At the same time, these messages starting occuring in /var/log/messages:
Code:
Dec 10 03:51:47 07 kernel: Mem-info:
Dec 10 03:51:47 07 kernel: Node 0 DMA per-cpu:
Dec 10 03:51:47 07 kernel: cpu 0 hot: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 0 cold: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 1 hot: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 1 cold: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 2 hot: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 2 cold: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 3 hot: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 3 cold: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 4 hot: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 4 cold: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 5 hot: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 5 cold: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 6 hot: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 6 cold: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 7 hot: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: cpu 7 cold: high 0, batch 1 used:0
Dec 10 03:51:47 07 kernel: Node 0 DMA32 per-cpu:
Dec 10 03:51:47 07 kernel: cpu 0 hot: high 186, batch 31 used:162
Dec 10 03:51:47 07 kernel: cpu 0 cold: high 62, batch 15 used:48
Dec 10 03:51:47 07 kernel: cpu 1 hot: high 186, batch 31 used:0
Dec 10 03:51:47 07 kernel: cpu 1 cold: high 62, batch 15 used:0
Dec 10 03:51:47 07 kernel: cpu 2 hot: high 186, batch 31 used:0
Dec 10 03:51:47 07 kernel: cpu 2 cold: high 62, batch 15 used:0
Dec 10 03:51:47 07 kernel: cpu 3 hot: high 186, batch 31 used:18
Dec 10 03:51:47 07 kernel: cpu 3 cold: high 62, batch 15 used:0
Dec 10 03:51:47 07 kernel: cpu 4 hot: high 186, batch 31 used:159
Dec 10 03:51:47 07 kernel: cpu 4 cold: high 62, batch 15 used:56
...
Dec 10 03:51:47 07 kernel: Node 3 HighMem per-cpu: empty
Dec 10 03:51:47 07 kernel: Free pages: 732052kB (0kB HighMem)
Dec 10 03:51:47 07 kernel: Active:4232128 inactive:3071288 dirty:158210 writeback:0 unstable:0 free:183320 slab:256840 mapped-file:289545 mapped-anon:3805487 pagetables:13063
Dec 10 03:51:47 07 kernel: Node 0 DMA free:10796kB min:4kB low:4kB high:4kB active:0kB inactive:0kB present:10356kB pages_scanned:0 all_unreclaimable? yes
Dec 10 03:51:47 07 kernel: lowmem_reserve[]: 0 3512 9067 9067
Dec 10 03:51:47 07 kernel: Node 0 DMA32 free:213332kB min:2500kB low:3124kB high:3748kB active:1794108kB inactive:1463220kB present:3596296kB pages_scanned:64 all_unreclaimable? no
Dec 10 03:51:47 07 kernel: lowmem_reserve[]: 0 0 5555 5555
Dec 10 03:51:47 07 kernel: Node 0 Normal free:41028kB min:3952kB low:4940kB high:5928kB active:3409444kB inactive:1471120kB present:5688320kB pages_scanned:0 all_unreclaimable? no
Dec 10 03:51:47 07 kernel: lowmem_reserve[]: 0 0 0 0
Dec 10 03:51:47 07 kernel: Node 0 HighMem free:0kB min:128kB low:128kB high:128kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no
Dec 10 03:51:47 07 kernel: lowmem_reserve[]: 0 0 0 0
Dec 10 03:51:47 07 kernel: Node 1 DMA free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no
...
Well to cut a long story short, I fixed the problem by disabling the swap partition with 'swapoff'. After about 30 mins all the swap was freed and the server went back to normal. I don't dare reactivate the swap partition and unfortunately as this is a live server which currently has no fail over, I can't reboot either
Server Spec:
4 * Dual-Core AMD Opteron(tm) Processor 8214
32GB DDR2 ECC RAM
RHEL 5.5, 2.6.18-194.11.3.el5 SMP x86_64
Running many KVM VMs (All CentOS x64) and kksmd is used.
bacula-dir Version: 5.0.0
IBM Tape Drive using lin_tape module version 1.34.0 according to modinfo
And before anybody asks
# sysctl vm.swappiness
vm.swappiness = 10
CentOS 5 :: Xmlrpc-c Server Free String Memory Alloc-ed By Xmlrpc_parse_value
Feb 24, 2010I have the following function on my xmlrpc server side.
The registration of this function is done as follows from the main function:
The above function makes the server segfault some where on the return path and client gets the response:
Here is what GDB shows when server segfaults....
However if I remove the line "xmlrpc_strfree (node_name);" then server does not segfault and client receives the response correctly. In the xmlrpc-c code it clearly says " Return the string in newly malloc'ed storage that Caller must free." in xmlrpc_data.c::xmlrpc_read_string() which is the function that gets called from xmlrpc_parse_value().
General :: Application Virtual Address Space Memory Allocation - Memory Does Not Get Free
Apr 20, 2010I am using malloc and frees a lot in my program. It shows its allocated but when i remove it doesnt show as the memory is removed(I am using the top command to view VIRT memory usage). If this continously grows what would happen to my program (Will it go out of memory?)
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May 3, 2011I am looking for free database that has low memory usage and innodb and memory like engins that has C API and support trigger and client/server support for using in embedded linux systems.
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Jun 16, 2010During playing around sources, synaptic playing I messed up the default list. I know I should have been more careful. Anyways could someone tell me what the default the default sources.list that has free and non free etc for squueze please? I have been trying to get the default list but I cannot find it anywhere. There are alot of lists out there but nothing tagged like the "default" list.
View 6 Replies View RelatedGeneral :: What Does Free Memory Mean In Top
Aug 5, 2009I would not exactly consider myself a newbie but this is a bit of a newbie question so here it goes.
When I run top I see used memory and free memory. When I first boot the system there is lots of free memory in about a day or two that memory whittles down from 2GB of Free mem(of 4GB) to 20MB and then maintains 20-50MB of free memory. This seems to be consistent across different servers. At first I thought there had to be some major memory leaks but it just seemed to prevalent to not have been noticed before.
I found a better way to gauge memory usage is the use of the free command. Now I am confused though, what is Free memory as it is defined and monitored in top?
Red Hat / Fedora :: Download Linux Redhat Version 4.0 Free?
Sep 24, 2010Is it possible to download linux redhat version 4.0 free..? If anyone provide me the link.
View 1 Replies View RelatedFedora :: Installing Free And Non-free Repositories?
Jan 28, 2011I've just installed Fedora 14 64bit and would like to add new repositories. I read here to do the following command (which as you can see doesn't works) :
Code:
$ su -c 'yum localinstall --nogpgcheck http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-stable.noarch.rpm http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-stable.noarch.rpm'
[code]....
Fedora :: Can't Install Rpmfusion Free And Non-free
Jan 28, 2011I have installed F14 yesterday but i can not install rpmfusion repository, the problem is that i can not access the url [URL] so i cant download the files:
rpmfusion-free-release-stable.noarch.rpm
rpmfusion-nonfree-release-stable.noarch.rpm
Ubuntu Installation :: FREE Support For FREE OS?
Jun 10, 2010Am I asking too much for a FREE OS? Everybody spend their precious time to help others, that's very helpful.But it seems like there is no support from UBUNTU team,how could we even get through the barrier of not using Microsoft's OSes? No free lunch of course, but it seems to me some issues have never really been solved.I read lot's of people have problem with their WIFI, not just for my OLD USB wifi adapter. I don't have problem with WIFI in XP/Server.
I posted here and there, and seems like no answer, and I do not get any reply from UBUNTU support team,forgive me if I run out of google's keywords.I just need a simple answer, is my WIFI going to work in UBUNTU with a layman effort? I like linux and UBUNTU had put great effort in providing me such a great OS, but if a basic internet connection will need to spent sooo much time to setup, and it still doesn't work. IS IT WORTH to switch to UBUNTU at all
Ubuntu :: Memory Is Not Occupied By Any Application But Not Free
Apr 15, 2010I have a very weird memory issue (as you may have guessed from the title). There's a discrepency between the memory accumulated by the various applications (using "ps -eF" to collect that) and the memory reported by system monitor/"free" Basically, I have around 0.5GB of memory that is not occupied by any application, but is not free as well. (It is not used as cache as well)
[Code].....
Red Hat / Fedora :: Find Actual Free Memory (RAM)?
May 10, 2011When we have Oracle 10g in RedHat, the free memory goes down soon after bootup of the system and never increases. I learnt from various forums that Linux does cache the disk files for the better performance. And when any application requires memory they get the memory and the caching does not block any memory. We want to capture the free memory available for one the harware planning activity.
1) When we use vmstat command, it gives very less free memory. since it caches large size files, the free memory is very low.
2) We tried free command, but how do we know how much actual free memory is available. i.e. excluding the cache usage
General :: How To Free Up Space - Memory Insufficient Error
Apr 25, 2010When I use top to see memory usage, I have 65gb ram but only 1.3gb of it free and remaining is shown as used. When I ran my program It gives memory insufficiency error. Although no other program is using the remaining 63.7gb ram it is hold. How can I get free the unused ram?
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Jul 12, 2011I'm trying to meter my memory usage. When I use these different programs, they all show me using different amounts of RAM.
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Jul 5, 2011im trying to collect some data. Is there a way to get the free memory stats over the past few days from some file... i looked into the sar log files but they dont have date stamps in them!
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Oct 22, 2015Whilst watching my system boot I see the following error:
'drm: radeon pci probe error kernel requires firmware non-free'.
When I install the ATI graphics driver, sure - I get all the screen resolutions I could possibly want, but the cost appears to be that it makes it causes my system to freeze at the user name and password screen. Sometimes the cursor blinks teasingly, but nothing appears as I type; sometimes the cursor itself is frozen.
My question isn't about the myriad of theoretical key combinations that might work - none of them have thus far.
I'm wondering whether I can simply continue using the default driver that the debian installer (ver. 8 stable 'Jessie') installed on my system. It's true that I only get 3 choices of screen resolution - 1152x864, 1024x768, and 800x600 - but my system seems so much more stable than when I install the proprietary ATI driver.
Aside from the login screen freezing - more often than not, strange things were happening keyboard wise - especially when composing posts for forums - the cursor would suddenly jump to another line of previously composed text for example!
So, can I keep the default driver or is it best to install the ATI driver and attempt to troubleshoot it? Is it even possible to troubleshoot a problematic driver - I knew how to do such things in Windows, but still learning about linux.
Also, when my system freezes at login (for whatever reason), if I'm obliged to simply hit the laptop power button to power down and press it again to restart - is this potentially damaging/corrupting my system - Debian, or indeed my hard drive?
Going forward, is the ATI driver issue likely be addressed in future Debian releases? Obviously, I would prefer to have the proper driver installed so as to have more screen resolution options - since I will be using my laptop for developing and testing web sites.
Networking :: Superuser Will Get Mail System Memory Free Status
Oct 7, 2010The superuser will get a mail about the system memory free status every minute after 9pm?
Which is Correct:
1. * 21 * * * free
2. * 21-0 * * * free
Software :: OPENNMS - Can Monitor Disk Space And Free Memory
Jul 16, 2011i had configured the opennms but i didint able to get the disk space and memory alert by mail... and also i need a plgin gor opennms can u tell me wat plugins suit for opennmms monitoring tool ...
View 2 Replies View RelatedProgramming :: Quick Measurement Of Free System Memory From Within C Program
Jul 21, 2010I need to monitor the amount of free physical memory on Linux from within a large C program. The sampling will occur very frequently, so the measurement cannot be performance intensive. The fact that Linux uses much of the theoretically free memory for cache and buffers means that just measuring the free pages is not sufficient. Using free + cache + buffers gives an overestimate as not all cache/buffers can be freed, but I could get a rough idea of how much generally can't and subtract that from the answer.
Possible options that I've come across so far are: Parsing /proc/meminfo - but that involves reading from file which is slow. Extracting the free, cache and buffers values from the output of the Free command - but is there a quick way to do this? Parsing the /proc/freemem file produced by the API here - but this is again reading from file. Is there a way to get that output directly? Speed is an extremely high priority, and the answer it must accurately represent the amount of memory that my program could expand into (to within a few Mb).
General :: Add / Of 3000mb In The Remaining 20380mb Free Space It Showing An Error Message That No Free Space Is Available
Jul 25, 2010I have 160gb laptop. i installed vista in c primary partition which is 25gb and installed ubuntu in d primary partition which is 20gb. A remainig for my data. Now i tried to install CENT OS by formatting ubuntu. I inserted CENT OS DVD and restarted and i selected to delete my /dev/sda2 which is showing 20480mb and it shown me free space. but i tried to add partion /boot of 100mb it got added. but, when i am trying to add / of 3000mb in the remaining 20380mb free space it showing an error message that no free space is available.
View 4 Replies View RelatedServer :: "free" Shows Far More Memory Usage Than Summing Up Application Usage?
Aug 6, 2010I've come across a really strange issue with one of my RHEL servers. The "free" command shows that 7019 MB of memory are actually in use by my system, but when summing up the actual usage (or even virtual usage like the example below) it doesn't add up - the sum is far less than what is reported by "free":
Code:
[root@server1 ~]# free -m
total used free shared buffers cached
Mem: 12011 7946 4065 0 4 23
-/+ buffers/cache: 7919 4092
[code]....
Server :: Clear Cache Memory ( RHEL 5.1 ) As It Consumes Almost 100% Physical Memory?
Jan 11, 2010let me know how to clear cache memory ( RHEL 5.1 ) as it consumes almost 100% physical memory.
View 3 Replies View RelatedUbuntu :: Log From Command Line - Free RAM Usage?
Sep 1, 2011Is it possible to narrow down the ram command to give me JUST the free ram? Both commands that I know give me much more information that I would like to log.
Code:
free -m
This line gives me this. I really only want the one under "free"
Code:
total used free shared buffers cached
Mem: 1262 612 649 0 250 114
-/+ buffers/cache: 247 1014
Swap: 4010 6 4003
Code:
cat /proc/meminfo
This line gives me this. I really only want "MemFree"
Code:
MemTotal: 1292372 kB
MemFree: 636088 kB
Buffers: 279032 kB
Cached: 118768 kB
SwapCached: 532 kB
Active: 191408 kB
Inactive: 324684 kB .....
General :: Source Code For Free Command?
Dec 8, 2009Where is the source implementation of the free command?
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