Solved

slow disk read/write problem over network.

Posted on 2012-12-29
9
695 Views
Last Modified: 2013-01-07
I have configured 4 SAS 15k RPM disks in RAID 1+0.
I ran read/write test using two simple benchmarket softwares downloaded from download.com. It shows that read/write to the drive locally shows;
read 600MB/s
write 580MB/s

Then I ran the same tests over network from multiple workstations, it shows;
read  6MB/s ~ 18MB/s
write 11MB/s ~ 40MB/s

I think there's some delay in network which causes the difference. Both ends of server and workstations have 1Gbps link. So, in theoretically, I expected somewhere between 50MB/s ~ 100MB/s for read/write. But it's way too lower.

What can it cause this delay and where should I start troubleshooting? Can it be some nic configurations on both end?

Both ends have auto negotiation and switch as well.
0
Comment
Question by:crcsupport
  • 3
  • 3
  • 2
  • +1
9 Comments
 
LVL 17

Assisted Solution

by:Gerald Connolly
Gerald Connolly earned 150 total points
ID: 38730491
What OS are you using? Is this an iSCSI setup or just a mapped drive?

A 1Gbps link is nominally 100MB/s but 50MB/s is a more realistic max due to the nature of Ethernet and the overhead of the protocol
0
 
LVL 3

Expert Comment

by:Teeshirt
ID: 38730686
Depends on which access layer switches you are using!
0
 
LVL 4

Expert Comment

by:wrwiii12
ID: 38730907
This would seem normal to me.  Your server drives are going to R/W a lot faster because they are designed to, whereas the desktop drives are going to be a slower format.  You gave the specs for the server drives which are high end drives but not the specs on the desktop drives.

I am guessing they will be PATA or SATA 5400 or 7200 RPM drives which will not be anywhere close to the 15k SAS drives.

Use a program called flash bench to test the drive speeds as it will not depend on your internet connection/network and that will give you the true speed results of your drives.
0
PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

 
LVL 3

Assisted Solution

by:Teeshirt
Teeshirt earned 150 total points
ID: 38730922
"as it will not depend on your internet connection/network and that will give you the true speed results of your drives. "

i strongly disagree.. I work in the Textile industry, we have designers uploading big files to shared folders at FULL network capacity.
0
 
LVL 1

Author Comment

by:crcsupport
ID: 38730958
OS is windows 2012 and workstations are windows xp. Correct, workstations have sata 7000RPM.

Is there any benchmark using buffer to test so that workstations' disk speed doesn't affect the speed test? I like to troubleshoot where exactly the problem is.
I also have SSD notebook, will bring in and do the same test if it does anything different.
0
 
LVL 1

Author Comment

by:crcsupport
ID: 38730977
switch is dell powerconnect 5448
workstations have various nic, intel pro 1000, etc in PCI or onboard., SATAI, SATAII...
0
 
LVL 4

Expert Comment

by:wrwiii12
ID: 38730978
There are many variables between everyones systems and networks.  You can have the fastest drives in the world in your computer but if your hardware bus speeds in the computer don't let it transfer at that rate then it wont utilize the full drive capacity.

I would suggest you download flash bench, which is a tool that runs directly on the system and tests file tranfer rates of both large and small files.  You don' t have to install it as it runs in memory and it is free.  This will give you the fastest rates that the drive/system will even allow.

Ok it looks like their site is down.  If you want to try this let me know and I will put it out there for you to download.
0
 
LVL 1

Author Comment

by:crcsupport
ID: 38731700
wrwiii12, can you put it somewhere to download?
thanks
0
 
LVL 4

Accepted Solution

by:
wrwiii12 earned 200 total points
ID: 38731720
0

Featured Post

Netscaler Common Configuration How To guides

If you use NetScaler you will want to see these guides. The NetScaler How To Guides show administrators how to get NetScaler up and configured by providing instructions for common scenarios and some not so common ones.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Telepresence on backup 3 29
laptop estate analysis 5 80
Sonicwall blocks a site 49 91
UPS and BTU calculation 3 49
Is your computer hacked? learn how to detect and delete malware in your PC
PRTG Network Monitor lets you monitor your bandwidth usage, so you know who is using up your bandwidth, and what they're using it for.
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
In this tutorial you'll learn about bandwidth monitoring with flows and packet sniffing with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're interested in additional methods for monitoring bandwidt…

808 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question