[PVE-User] Very slow server (RAW IDE discs and KVM)

Erik van Ast Erik.van.Ast at suzohapp.nl
Thu Aug 11 14:08:40 CEST 2011


Hi all,

I removed the machines that were creating problems and I also deleted the backup job. The system is still very slow when creating a new VM, but I still can't figure out why.

This is the status of the server Atop shows when running only the 2008 machine (106:but being only "idle") :

proxmox:~# atop
ATOP - proxmox            2011/08/11  13:13:51               10 seconds elapsed
PRC | sys   0.19s | user   0.29s | #proc    132 | #zombie    0 | #exit      0 |
CPU | sys      1% | user      1% | irq       0% | idle    395% | wait      4% |
cpu | sys      0% | user      0% | irq       0% | idle     96% | cpu002 w  4% |
cpu | sys      0% | user      0% | irq       0% | idle     99% | cpu000 w  0% |
cpu | sys      0% | user      0% | irq       0% | idle     99% | cpu001 w  0% |
CPL | avg1   0.45 | avg5    0.44 | avg15   0.37 | csw    45320 | intr   33065 |
MEM | tot    7.8G | free    4.4G | cache  45.5M | buff   24.5M | slab   73.7M |
SWP | tot    7.0G | free    7.0G |              | vmcom   3.3G | vmlim  10.9G |
DSK |         sda | busy      6% | read       3 | write     33 | avio   16 ms |
NET | transport   | tcpi       1 | tcpo       2 | udpi       0 | udpo       0 |
NET | network     | ipi       32 | ipo        4 | ipfrw      0 | deliv     14 |
NET | tap106   0% | pcki      18 | pcko      54 | si    2 Kbps | so    6 Kbps |
NET | eth0     0% | pcki      54 | pcko      22 | si    6 Kbps | so    4 Kbps |
NET | vmbr0  ---- | pcki      55 | pcko       4 | si    4 Kbps | so    1 Kbps |

  PID  SYSCPU  USRCPU  VGROW  RGROW  RDDSK  WRDSK  ST EXC S  CPU CMD     1/1
 2533   0.16s   0.29s     0K     0K    24K   182K  --   - S   5% kvm
 2659   0.02s   0.00s     0K     0K     0K     0K  --   - R   0% atop
 2079   0.01s   0.00s     0K     0K     0K     0K  --   - S   0% rsyslogd
 1963   0.00s   0.00s     0K     0K     0K     0K  --   - S   0% iscsid

When creating a new 2003 machine (102) which is "installing devices" at the moment of this screencapture. Installing devices is normally not very intensive to do, but the disc has been between 90-99% all the time when installing this new machine :
proxmox:~# atop
ATOP - proxmox            2011/08/11  13:52:01               10 seconds elapsed
PRC | sys   0.35s | user   0.83s | #proc    133 | #zombie    0 | #exit      0 |
CPU | sys      2% | user      4% | irq       0% | idle    274% | wait    121% |
cpu | sys      1% | user      2% | irq       0% | idle     52% | cpu000 w 45% |
cpu | sys      0% | user      1% | irq       0% | idle     34% | cpu001 w 65% |
cpu | sys      0% | user      1% | irq       0% | idle     98% | cpu003 w  1% |
cpu | sys      0% | user      0% | irq       0% | idle     90% | cpu002 w  9% |
CPL | avg1   1.42 | avg5    1.51 | avg15   1.38 | csw    92874 | intr   68089 |
MEM | tot    7.8G | free    1.9G | cache 478.7M | buff   34.3M | slab  112.5M |
SWP | tot    7.0G | free    7.0G |              | vmcom   5.3G | vmlim  10.9G |
DSK |         sda | busy     99% | read      11 | write    260 | avio   36 ms |
NET | transport   | tcpi     137 | tcpo     200 | udpi       0 | udpo       0 |
NET | network     | ipi      149 | ipo      200 | ipfrw      0 | deliv    144 |
NET | tap106   0% | pcki     218 | pcko     234 | si   32 Kbps | so   42 Kbps |
NET | tap102   0% | pcki       0 | pcko      31 | si    0 Kbps | so    2 Kbps |
NET | eth0     0% | pcki     328 | pcko     416 | si   49 Kbps | so  135 Kbps |
NET | vmbr0  ---- | pcki     124 | pcko     156 | si    7 Kbps | so   99 Kbps |
NET | lo     ---- | pcki      44 | pcko      44 | si   12 Kbps | so   12 Kbps |
  PID  SYSCPU  USRCPU  VGROW  RGROW  RDDSK  WRDSK  ST EXC S  CPU CMD     1/1
 2533   0.15s   0.39s     0K     0K     0K   117K  --   - S   5% kvm
 2743   0.17s   0.36s     0K     0K    56K   820K  --   - S   5% kvm
 2607   0.00s   0.04s     0K     0K     0K     8K  --   - S   0% pvedaemon
 2807   0.00s   0.02s     0K     0K     0K     0K  --   - S   0% apache2
 2808   0.00s   0.02s     0K     0K     0K     0K  --   - S   0% apache2
 2659   0.02s   0.00s     0K     0K     0K     0K  --   - R   0% atop
 2753   0.01s   0.00s     0K     0K     0K     0K  --   - S   0% qm
 2609   0.00s   0.00s     0K     0K     0K     0K  --   - S   0% pvedaemon
   15   0.00s   0.00s     0K     0K     0K     0K  --   - R   0% events/0
 1752   0.00s   0.00s     0K     0K     0K    12K  --   - S   0% kjournald
 2545   0.00s   0.00s     0K     0K     0K     0K  --   - S   0% flush-254:2

How can I check if there is still a backup or another process running in the background that is causing these performance problems. Only 2 VM's are currently running and one of them is installing and the other is idle, so the server has not much to do... The proxmox server has also been restarted before I started creating the new 2003 machine...

Kind regards,
Erik   

-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Message: 1
Date: Thu, 11 Aug 2011 10:46:27 +0200
From: "Erik van Ast" <Erik.van.Ast at suzohapp.nl>
To: <pve-user at pve.proxmox.com>
Subject: Re: [PVE-User] Very slow server (RAW IDE discs and KVM)
Message-ID:
	<80A72F1B1CFF80409D8E422437CEDC9A02537F91 at srv03-suzo-03.Suzo.int>
Content-Type: text/plain;	charset="iso-8859-1"

Hi Muhammad,

Thank you for your reply. This might be the problem I am facing now, because I tested a couple of backup options and both machines are backed up every night.
Does anyone have experience with this? I will search big friend Google now, but if someone knows what to do exactly, please let me know...

Met vriendelijke groet / Kind regards / Mit freundlichem Gru?, _______________________________________________________________

Erik 
------------------------------

------------------------------

Message: 2
Date: Thu, 11 Aug 2011 14:45:30 +0500
From: Muhammad Yousuf Khan <sirtcp at gmail.com>
To: Erik van Ast <Erik.van.Ast at suzohapp.nl>
Cc: pve-user at pve.proxmox.com
Subject: Re: [PVE-User] Very slow server (RAW IDE discs and KVM)
Message-ID:
	<CAGWVfM=T0EKKBHYrJhgP0T9ZbhsxjVMDZknGBNZYOxRBL97XfQ at mail.gmail.com>
Content-Type: text/plain; charset="iso-8859-1"

perhaps i got the catch here actually you might be backing up 180 GB of data as you said your VM is 180GB in size. so backup up that amount of data will kill your IO and chock the bandwidth. Heavy (Big virtual HD) machines as VMs are not recommended since backup should be the problem. even-though you are running the whole system on a Desktop machine. i am also running one machine with the same config as yours in production. my machine contains 7 VMs of different OS flavor Linux and windows. however all of them are lesser then 25 GB. i am running this whole bunch for about more then 3 months and never had the performance issue, by limiting the bandwidth and using less GBs for Virtual Hard disks.

u can limit the bandwidth by following the instructions below..

Create the /etc/vzdump.conf file with the following content:

bwlimit: 5000

Now Fileserver part. You can use separate hardware machine for the fileserver if you wanted to use VM just in any case then try to use NAS solutions. there are few very good popular and free NAS solutions out there like FreeNAS and Openfiler. i am using Openfiler you can always Attach NFS or ISCSI to your VMs as a native facility of those NAS boxes. although ISCSI is not recommended by me if you are using desktop machine as a NAS BOX because you will not reach throughput of your actual LAN. anyways it is out of topic. i hope this helps



Thank you,



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