top is a Unix/Linux/BSD program to show what processing are running. It can show the top users of CPU or memory.

learn more… | top users | synonyms

24
votes
3answers
17k views

Linux - How can I see what's waiting for disk IO

I have a server that has a really high load. Nothing is jumping out at me in terms of CPU usage, and it's not swapping. I think it's cause some processes are waiting for disk IO, and I want to see ...
0
votes
0answers
12 views

Why top output different from sar output?

This is SLES11sp3 system. The command top shows the load average of 17+, as shown below: #top top - 11:59:14 up 19 days, 21:55, 40 users, load average: 17.09, 17.29, 19.22 Tasks: 514 total, 1 ...
3
votes
3answers
3k views

tail: inotify cannot be used, reverting to polling: Too many open files

tail: inotify cannot be used, reverting to polling: Too many open files I'm running apache and tomcat servers on Ubuntu (AWS ec2). Whenever I try to tail the catalina.out of tomcat I get too many ...
1
vote
1answer
45 views

how can I understand why apache is consuming so much cpu - ec2

I have an ec2 c3.medium instance running. It has recently started maxing out the cpu making the server unresponsive. Rebooting the instance doesn't really help for long, although it does make apache ...
1
vote
2answers
5k views

ps shows that migration/* processes consume a lot of CPU, but top keep silence about them

here is the result of ps command, shown only first 10 lines ps aufx | head USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 2 0.0 0.0 0 0 ? S ...
1
vote
2answers
973 views

top command - cpu from processes do not add up

I understand the various types of cpu usage reported by the top command (6.5%us, 17.2%sy, 0.0%ni, etc...), but why does the total %CPU for each process not add up to any of the Cpu(s) values? For ...
1
vote
1answer
124 views

System not being able to handle soft interrupts but having idle time?

I have a constant 5% and more CPU time spent in handling soft interrupts. Doe to that, the ksoftirqd is running almost constantly, but is using a very small amount of CPU (less than 1%). However, ...
1
vote
1answer
41 views

Influence of kernel code execution to Load average in top?

I'm trying to tests the amount of CPU that iptables use for NAT. Perhaps it will be more accurate to say "the amount of CPU that the netfilter kernel module" uses. The approach i took was to try and ...
-1
votes
3answers
131 views

free shows more memory used than top process total

UPDATE: This was being caused due to a known issue with nss-softkn. See this article: https://www.splyt.com/blog/2014-05-16-optimizing-aws-nss-softoken When I run free -m from my centos 6.5 box I ...
2
votes
1answer
33 views

How to spec VM requirements based on historical data of transient processes on Linux?

I've been given a task to break apart the services on one of our main VMs (Amazon EC2) and appropriate additional VMs to suit the services needs. The type of services that I am dealing with are ...
0
votes
0answers
32 views

How to reset CPU counters? [duplicate]

I have a Linux server (Debian 2.6.32-46-amd64) which has been online for 117 days. The server is basically an Apache + MySQL, and MySQL was usually at 100~200% CPU usage (using top) being the server ...
1
vote
1answer
110 views

ps_mem.py vs top - memory usage?

Every now and again my apache server is crashing, getting an error saying the MaxClients has been reached. In my research I've gained the impression that I may be running out of memory (just checked ...
1
vote
3answers
125 views

Find out what NFSD processes are actually doing?

When I view top on one of our servers there are a lot of nfsd processes consuming CPU: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 2769 root 20 0 0 0 0 R ...
0
votes
0answers
59 views

aws stolen cpu on dedicated machine

I'm running a dedicated m3.medium EC2 instance. How is it possible that my top says: Tasks: 84 total, 1 running, 83 sleeping, 0 stopped, 0 zombie Cpu(s): 4.3%us, 1.5%sy, 0.0%ni, 90.8%id, ...
8
votes
3answers
20k views

Something eats all memory (I suspect memory leak on some app). How to detect what?

I have server which runs liquidsoap+icecast bundle and simple website (httpd+mysqld). Nothing special. Visitors around 2000+ per day, with around 50 being online simultaneously on average. Server has ...
8
votes
5answers
14k views

How to have linux top command show memory summary in megabytes not kilobytes

Redhat EL5 I had my top configured the just the way I like showing the memory summary and swap summary in MB. I had to close my shell and then when I re-opened it, it is back showing in (default ?) ...
-1
votes
1answer
48 views

Memory on dedicated server is filled out [duplicate]

We are managing a dedicated server (WHM/cPanel) with 4-5(Magento & Woocommerce mostly) accounts in it, along with custom code that will connect those platforms with ERPs. This custom code works a ...
4
votes
3answers
149 views

On a freshly-rebooted server why would the CPU running time of processes be huge?

I rebooted our server this morning, yet there are umpteen processes that appear to have been running for 600+ days? Could someone please shed some light? The datetime of the machine is correct: ...
103
votes
2answers
43k views

What exactly do the colors in htop status bars mean?

By default, htop shows colored status bars for processors, memory, and swap. From left to right, the bars are colored green, blue, yellow, and red depending on some thresholds. What does it mean when ...
3
votes
2answers
2k views

How to exclude some users from Linux Top screen?

In top screen, by default it shows all users' processes. How to exclude some users(for example, root and nobody) from the top real-time screen?
0
votes
1answer
45 views

How to understand details of CPU usage

I have a VPS server. At the CPU usage chart I see long periods of 50% CPU usage that are not related to chart of visitors of my site: http://c2n.me/iRJplq. I checked top and most of the time fastcgi ...
2
votes
3answers
6k views

TIME+ column in top command is inaccurate

I just ran the top command to observe the following process chown -r me:me allMyMusic And it's been running for about 5 minutes, however the TIME+ column in the top command has reported it as ...
1
vote
2answers
397 views

Live monitoring on web server logs by tailing the webserver access log

I am looking for a way to find who causes high load on my nginx web server but I do have too many requests per minutes to figure it out which one is the real cause. I want a solution that would work ...
0
votes
1answer
109 views

Apache TOP command time format?

When running top on an Apache server, what is the time format for the output? For instance, is it minute:second.second? http://i.imgur.com/wBx8PAh.png Edit: I'm running on Ubuntu 14.04 and the ...
1
vote
2answers
66 views

Something like `top` for vhosts

Is there any way of establishing what vhosts are keeping Apache processes busy, in real time? Ideally I'd like a tool like top (or htop) that shows me which sites are busiest, or most costly, right ...
0
votes
3answers
616 views

Top not showing processes using CPU resources

I have this output from top for the top 10 processes sorted by CPU usage descending: top - 11:19:58 up 1:46, 2 users, load average: 3.22, 3.48, 3.34 Tasks: 66 total, 5 running, 61 sleeping, ...
1
vote
1answer
386 views

How to get atop to create daily logfile

I'm running a website on a VPS running Centos 6.5 and am having some issues. I'm new to serveradmin so just learning. atop was already installed on our machine and it's working. I wanted to go in and ...
0
votes
2answers
146 views

Is there a top like tool that shows processes and ports, live?

I'd like to be monitoring ports in "realtime" and the processes that use them. Is there any tool that can handle that? I imagine somethinkg like top, but with a column that lists all ports the process ...
0
votes
0answers
86 views

high mysqld cpu usage after moving to new server

Just moved to a new (more powerful) server with only one website running on it, no changes on the website, but now I got a horrible high CPU load and I can't find out why. top: top - 22:54:08 up 1 ...
1
vote
2answers
1k views

memory leak? RHEL 5.5. RSS show ok, almost no free memory left, swap used heavily

i encounter a very instresting problem, and it seems that some physical may disapper quietly. i am very puzzled, so if anyone could give some help, I would be very appreciated. here is my top show: ...
1
vote
2answers
342 views

top and htop disagree on memory usage, but swap is being used on GlusterFS server. Can this be improved?

If I run free -m, top and htop, I get different memory uses. The system is also using a small amount of swap. I understand from this question why they are reporting different values (some of the data ...
2
votes
1answer
176 views

Our RAM usage is high, including -/+ buffer/cache, but top has no answers

We are running CentOS 6 with a PHP web application. After we pushed a new version live it seems we have a memory issue, however top does not show any high usage instances. I have looked around and ...
0
votes
1answer
181 views

CentOS 6.4 64-bit Memory Usage really not adding up

I recently migrated hosting providers and in the process my distribution changed from CentOS 5.9 64-bit to CentOS 6.4 64-bit. Despite having a little more RAM (1 GiB rather than 768 MiB) the new VPS ...
19
votes
1answer
9k views

Why does htop have three load averages?

On htop, it shows three load averages, one bold, one normal, one red. What do they signify?
0
votes
0answers
50 views

Strange load average behaviour

We have a daemon which collects system data and writes it into database. Sometimes the load average goes very high without apparent reason. Here is sample output. | id | server_id | datetime ...
1
vote
2answers
2k views

nginx+php-fpm help optimize configs

I have 3 servers. First server (CPU - model name: 06/17, 2.66GHz, 4 cores, 8GB RAM) have nginx as load balancer with next config upstream lb_mydomain { server mydomain.ru:81 weight=2; ...
4
votes
2answers
356 views

How to read `top`. Process list says processes have swap but overview says no swap is being used

I am using top to monitor my server. The swap row reads Swap: 1044220k total, 0k used, 1044220k free, 148544k cached I have hit O p to sort by swap. PID USER PR NI VIRT RES ...
4
votes
4answers
4k views

How do I increase size of Terminal on Linux

I have a 48core linux box. I would like to monitor per core cpu usage. However when I use top and press 1 I get an error message "Sorry, terminal is not big enough" Is there anyway I can increase ...
0
votes
2answers
509 views

How can I find out what Zimbra process (specifically “b”) is doing?

My Zimbra mail server (8.0.2 Community Edition) recently started to spawn an interesting process called "b". top - 11:04:44 up 19 days, 18:47, 1 user, load average: 6.25, 6.38, 5.57 Tasks: 131 ...
0
votes
1answer
250 views

What does TOP's DATA column mean?

I'm trying to figure out the meanings of all the different classifications of memory such as VIRT, RES, SHR, AND DATA. While I generally understand the first 3, I have no idea what the DATA column ...
0
votes
0answers
43 views

top output seems fine, yet server is overloaded

This server I am benchmarking gives no obvious signs of getting overloaded at a first glance. top output: top - 22:48:25 up 5 days, 3:41, 3 users, load average: 3.19, 3.34, 3.25 Tasks: 146 total, ...
2
votes
1answer
106 views

How to interpret increasing SHR reported by top?

The man page for top defines SHR as: t: SHR -- Shared Mem size (kb) The amount of shared memory used by a task. It simply reflects memory that could be potentially shared with other ...
3
votes
1answer
476 views

Measuring load - %CPU in top is different than %us

When I run TOP on a remote server, I see a very small system utilization (3.8%us). However, for the actual process I am seeing 29.6% of the CPU. Since this server has 8 CPU cores, is the %CPU the ...
2
votes
0answers
195 views

linux - Debian - top(1) in batch mode, with selected columns

I have read the man page (which does not mention how to select columns in batch mode but explains how to do it in interactive mode). Since I also have seen blogs discussing how some environment ...
-1
votes
2answers
148 views

What does top report in a Linux-VServer

So if im logged into a linux-vserver and run the command top. Is the fields 'load average' and cpu's for the virtual server or the host machine?
4
votes
1answer
2k views

MongoDB virtual memory usage

I'm testing MongoDB for archives data. We have a collection with 160M rows. MongoDB instance takes 76.2 Gb virtual memory on a 12 Gb physical memory box ;-) The swap in null. I read that virtual ...
-1
votes
1answer
626 views

Top not accurately showing memory usage [duplicate]

Top is not showing my memory usage accurately or is my VPS provider doing something strange? As you see in the picture bellow it uses 90%+ of the memory, but when you look at what processes that is ...
1
vote
1answer
162 views

Load average 1.00 while top seems to show the server as idle

My server is not responding to HTTP requests, and it took me a long time before being able to log in with SSH; it all looks like the server is overloaded and on its knees. It already did that a few ...
12
votes
2answers
4k views

How is memory usage reported in Linux?

Using ps, I can see the size, the vsize (same as top's VIRT?), and the rss (same as top's RES?). (One more I see in top is SHR.) Could someone summarize for me what these different fields mean?
1
vote
1answer
119 views

How to find cause of EC2 micro instance regular read/write surge?

Every day without fail, sometime between 06:20 and 07:00 UTC, I get two email alerts from EC2 warning me that my "High VolumeWriteBytes" and "High VolumeReadBytes" have exceeded my set threshold. I ...