Visit Our UNIX and Linux User Community


Hard Disk Performance issues Suse 11 SP1


 
Thread Tools Search this Thread
Top Forums UNIX for Dummies Questions & Answers Hard Disk Performance issues Suse 11 SP1
# 1  
Old 08-21-2013
Hard Disk Performance issues Suse 11 SP1

hi guys

right now I have 6 Virtual Machines (VMs) running on Vmware ESXi 5.1 and attached to Storage SAN.
All these run Suse Linux 11 SP1 x64.

All of a sudden 1 of these VMs is running very slow making high CPU usage and I see al wait % kinda high 40-50%. Apparently since I don't own this virtual server the server was running fine and last change made was increasing memory

so I found out that test hard disk performance must be the issue
VM having issues. It so slow that I cancel the command but it's running at 2.7 MB

Code:
dd if=/dev/zero of=test bs=1048576 count=2048
781+0 records out
818937856 bytes (819 MB) copied, 298.699 s, 2.7 MB/s

running dd command on any of the other VMs linux server is about 280MB - 310 MB/s

Code:
dd if=/dev/zero of=test3 bs=1048576 count=2048
2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 7.64361 s, 281 MB/s

any idea what could be causing this issue or how to fix it?

thanks a lot
# 2  
Old 08-22-2013
It's hard to tell without access to server.

You might want to check the iostat output on the machine.
If the values are high, check the machine for processes doing intensive disk operations.

Also, you might want to check on your storage if the actual spindles (physical disks) are being shared to some other hosts doing intensive I/O.

Check the FC switch port for possible errors.

Regards
Peasant.
This User Gave Thanks to Peasant For This Post:
# 3  
Old 08-22-2013
Quote:
Originally Posted by Peasant
It's hard to tell without access to server.

You might want to check the iostat output on the machine.
If the values are high, check the machine for processes doing intensive disk operations.

Also, you might want to check on your storage if the actual spindles (physical disks) are being shared to some other hosts doing intensive I/O.

Check the FC switch port for possible errors.

Regards
Peasant.
I already moved the VM to another storage another SAN zone so taking storage out of question, well I have really really fast storage working on this
# 4  
Old 08-22-2013
It seems this can happen after a move of the VM.
Work-around: switch auto-move off for SuSE VMs. Manually move them, and reboot them if performance becomes bad and/or system load becomes high.
This User Gave Thanks to MadeInGermany For This Post:
# 5  
Old 08-22-2013
Quote:
Originally Posted by MadeInGermany
It seems this can happen after a move of the VM.
Work-around: switch auto-move off for SuSE VMs. Manually move them, and reboot them if performance becomes bad and/or system load becomes high.
do you mean storage vmotion? or anotehr setting?

thanks a lot
# 6  
Old 08-23-2013
Maybe even short stops can cause this. In this case - yes.
 

Previous Thread | Next Thread
Test Your Knowledge in Computers #483
Difficulty: Easy
IDEs do not provide automated compile/build features and other tools that make the software development process easier and faster.
True or False?

7 More Discussions You Might Find Interesting

1. SuSE

Personal SUSE build installation issues.

http://uploads.tapatalk-cdn.com/20160725/0174562490859032f68430fb0fa216cd.jpg I have created a personally made SUSE-based distro using susestudio.com and it will install just fine on my laptops (32-bit Acer Aspire One ZG5 and MacBook 4,1). However, when installing on an old Emachine desktop, I... (6 Replies)
Discussion started by: TheOuterLinux
6 Replies

2. Solaris

Getcwd performance issues

Hello everyone, recently we have been experiencing performance issues with chmod. We managed to narrow it down to getcwd. The following folder exists: /Folder1/subfol1/subfol2/subfol3 cd /Folder1/subfol1/subfol2/subfol3 truss -D pwd 2>&1 | grep getcwd 0.0001... (4 Replies)
Discussion started by: KotekBury
4 Replies

3. UNIX for Dummies Questions & Answers

GCC on suse 10 SP1

hi guys I use rpm -qa to find installed packages in red hat centos.... but how to do it in Suse 10 SP1 for instance? specifically I need to find if gcc installed thanks a lot (1 Reply)
Discussion started by: karlochacon
1 Replies

4. Linux

C++ Code to Access Linux Hard Disk Sectors (with a LoopBack Virtual Hard Disk)

Hi all, I'm kind of new to programming in Linux & c/c++. I'm currently writing a FileManager using Ubuntu Linux(10.10) for Learning Purposes. I've got started on this project by creating a loopback device to be used as my virtual hard disk. After creating the loop back hard disk and mounting it... (23 Replies)
Discussion started by: shen747
23 Replies

5. Solaris

Hard disk write performance very slow

Dear All, I have a hard disk in solaris on which the write performanc is too slow. The CPU , RAM memory are absolutely fine. What might be reason. Kindly explain. Rj (9 Replies)
Discussion started by: jegaraman
9 Replies

6. SCO

declare disk driver for IDE hard disk

hi I've a fresh installation of SCO 5.0.7 on the IDE hard disk. For SCSI hard disk I can declare, for example blc disk driver using: # mkdev hd 0 SCSI-0 0 blc 0but it works for IDE hard disk? (3 Replies)
Discussion started by: ccc
3 Replies

7. UNIX for Dummies Questions & Answers

Awk Performance Issues

Hi All, I'm facing an issue in my awk script. The script is processing a large text file having the details of a number of persons, each person's details being written from 100 to 250 tags as given below: 100 START| 101klklk| ... 245 opr| 246 55| 250 END| 100 START| ... 245 pp| 246... (4 Replies)
Discussion started by: pgp_acc1
4 Replies

Featured Tech Videos