Sudden slow in access

[edhan]

Using the D-link 323 with 2 units of 1.5TB harddisks. It was working fine for 6 months, but suddenly it is slowing down alot while accessing files and working with it. This device is serving between 6 - 8 users at the same time. Hook up with a 24-ports 1GB switch and Cisco router.

There are 4 computers using 1GB network adaptors while the rest are using 100Mbps adaptors. It happens about a month ago when the files accessing is sluggish and slow. Nothing has been changed which is puzzling why this is happening.

Is there a way to monitor why the access using Excel is slow? Or software that can tell where is the bottleneck?

[lpoulsen]

While I am not familiar with the D-Link device, I am guessing that one or more of the following have happened:
- the amount of data stored on the device may have grown to where the active working subset of data no longer fits in memory, and disk is being accessed where it wasn't before
- the drives may have become fragmented
- you may have network problems (packet loss) so that data transfers routinely invoke retransmission delays

Performance problems are always difficult to troubleshoot in a forum such as this, because you do not tell us what performance you are actually getting versus what you are expecting.

What is the typical aggregate transfer rate that you are getting from you NAS ? (In megabytes per second).

[MrGamm]

I don't know, but is it specifically with Excel and not other programs? Maybe copying files is still just as fast, but now opening an working with files is slow?

I am not fluent with Excel, but maybe memory is low and they are large files and Excel is using a remote scratch disk for virtual memory instead of a local one?

[edhan]

- the amount of data stored on the device may have grown to where the active working subset of data no longer fits in memory, and disk is being accessed where it wasn't before
- the drives may have become fragmented
- you may have network problems (packet loss) so that data transfers routinely invoke retransmission delays

Performance problems are always difficult to troubleshoot in a forum such as this, because you do not tell us what performance you are actually getting versus what you are expecting.

What is the typical aggregate transfer rate that you are getting from you NAS ? (In megabytes per second).

Disk storage is still low as it is only using about 30 GB for the 1.5 TB harddisk.

Seems like I am unable to defrag the harddisk as it is a network drive. I am still looking for a method to defrag. From what I understand, this network drive is formatting the 1.5 TB harddisk in linux format and not ntfs.

I checked with the D-link support and their staff said that they are 56 users in their company using the single DNS 323 network drive and have no issue of traffic. That is why I can't understand the logic of it being slow.

The performance of accessing the Excel used to be around 5 - 10 secs when you click to open a file or saving it. But now it takes 2 - 3 minutes. That is why it is so strange.

[edhan]

I don't know, but is it specifically with Excel and not other programs? Maybe copying files is still just as fast, but now opening an working with files is slow?

I am not fluent with Excel, but maybe memory is low and they are large files and Excel is using a remote scratch disk for virtual memory instead of a local one?

The files are not huge. Each system has 4 GB SDRAM. When work locally on the computer, there is no issue. But when work on the network drive, this is getting to be slow.

[weegillis]

@edhan: Recently my ISP pushed an update onto my gateway router. For several days/weeks I've had strange behavior in my internet connection. Today I discovered the change, reset the router and haven't had any problems since. It's not a D-Link, but perhaps this is all you need to do also? Log onto your router and reset it from the control panel. I don't know what effect a manual reset (button on modem) would have, but on top of wiping everything out, probably the same.

[edhan]

@weegillis: I think you have mistaken of what I was asking. I am not referring to internet access as that is fine. But what I was asking is accessing files with Excel through network using the 1GB network switch and 1GB network adaptors connection.

[MrGamm]

The files are not huge. Each system has 4 GB SDRAM. When work locally on the computer, there is no issue. But when work on the network drive, this is getting to be slow.

Well... if it helps, it seems there is alot on the internet specifically a problem with slow opening excel files.

Here is one with a solution.

http://excel2007-slow-open-file.blogspot.com/

I am guessing that during the microsoft excel installation process they are installing a lighter version of the software with less add-ons, so it is probably something that is a problem with the way the code works that they have not fixed?

Maybe a programmer used a technique that worked fine for them in a local environment but when moving the software to a network drive it drains too many resources?

I don't use excel, but maybe if the spreadsheets are not too complicated, OpenOffice might be something to try?

http://www.openoffice.org/

That is what I use when I need to. Just to see if you can isolate the slow performance to a specific application, or if it is indeed a problem with the network?

[weegillis]

@weegillis: I think you have mistaken of what I was asking. I am not referring to internet access as that is fine. But what I was asking is accessing files with Excel through network using the 1GB network switch and 1GB network adaptors connection.

There's no fun if you don't step in it! LOL

[edhan]

@MrGamm: Thanks. I have read most of the Excel problems in the internet but none of them is related to my issue. In internet, most of the users are having problems locally using on their PC. But for my case, it is fine except in the network situation. I do believe in the network environment, it is always complicated as there are too many variable. I am intending to eliminate one at a time but can't seem to figure out after many attempts. Thanks anyway.