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Questions tagged [vmstat]

CLI tool that reports information about processes, memory, paging, block IO, traps, and cpu activity

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Find out which task is generating a lot of context switches on linux

According to vmstat, my Linux server (2xCore2 Duo 2.5 GHz) is constantly doing around 20k context switches per second. # vmstat 3 procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu---- r b swpd free buff cache si…
grzaks
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Performance Tuning a High-Load Apache Server

I am looking to understand some server performance problems I am seeing with a (for us) heavily loaded web server. The environment is as follows: Debian Lenny (all stable packages + patched to security updates) Apache 2.2.9 PHP 5.2.6 Amazon EC2…
futureal
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How would you interpret the following vmstat output?

Consider the following five machines (named c, h, j, s and u) and their respective vmstat 1 outputs. Given the information from the vmstat output: Which machines would you consider being in a good shape? Why? What's your reasoning? Which machines…
knorv
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How to get % memory usage with vmstat?

I need to get a memory usage in % from vmstat, but I don't quite understand some of the numbers relating to memory displayed in vmstat. In particular, given an output like this procs -----------memory---------- ---swap-- -----io---- --system--…
His
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Server load high, CPU idle. NFS the cause?

I am running into a scenario where I'm seeing a high server load (sometimes upwards of 20 or 30) and a very low CPU usage (98% idle). I'm wondering if these wait states are coming as part of an NFS filesystem connection. Here is what I see in…
Mech
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On Linux, what is the size of pages reported by vmstat command and/or /proc/vmstat?

As many have stated on StackExchange and elsewhere, a typical kernel/mmu page size for Linux is 4 KiB. I have verified that this is the case on my OS/architecture (RHEL 6.6, Intel Xeon E5-2690). Now among other things, the vmstat -s command reports…
Marc C
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determining free memory from command line on Windows

I would like to monitor the free memory on four machines each running Windows Server 2003 R2 SP2 64-bit. Each box has 31.7gb of RAM. I would like to periodically run a command line tool so I can collect the output and later make charts with it. I…
Nate
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Interpretation of non-zero vmstat "si/so" values

What are useful rule-of-thumbs with regard to interpreting non-zero vmstat "si/so" values? When are the values "okay" and when are they an indication of that the memory situation is problematic? The question is of course hard to answer in the…
knorv
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awk on vmstat to get si,so

I am writing a shell script to check the vmstat si and so data at various time intervals vmstat 1 sample output: procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu---- r b swpd free buff cache si so bi bo …
APZ
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vmstat -f shows large number of forks

I have a production server that is showing a very large number of forks when running vmstat -f. Any suggestions on steps that could be used to help find out what the origin of the forks are? vmstat -f 1 6650796 forks EDIT: [~]$ ./forks.sh…
Taylor Leese
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Reporting historical system activity in FreeBSD

I'd like to record data about system activity under FreeBSD for future analysis. If I were running a SysV system, I'd just sar and its related utilities, but that doesn't exist in the BSDs. (And bsdsar has gone missing.) I don't really care about…
wfaulk
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Top showing 64% idle on first screen or batch run, while there is no idle time at all

I'm running a quite heavy number crunching thing on a few 4 core servers, all running Ubuntu Precise Pangolin LTS 64 bit, in the cloud (so I suppose in a virtualized environment). To monitor the cpu usage, i wrote a .sh that uses "top -b -n 1" (that…
Simone Gianni
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Getting CPU steal times on Ubuntu 11.4 Virtual Box

I'm trying to check on CPU steal times in a virtual machine. The goal is for me to be able to detect if my app is running in a VM on over-committed hardware. I'm currently just testing, in preparation for later production. I was trying to test this…
ThoughtfulHacking
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The CPU idle is set to 99 while using vmstat, what does this mean?

I am confused with the CPU idle time is set to 99. Does this mean the CPU is idle not doing anything for 99% of the time? #vmstate procs -----------memory---------- ---swap-- -----io---- --system-- -----cpu------ r b swpd free buff cache …
Mark k
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Chop headers off of vmstat command?

Is there a way to run the VMSTAT command (or something like it) and have a timestamp be included in the line? I know that I can pipe the output of the command and manipulate the results, but if I do that, I'll get junk information; I'm told that…
IVR Avenger
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