Perplexing hard drive transfer rate issue ?!

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Hi

I have a weird problem that maybe some one can shed some light on?

I have a Samsung F1 1tb drive and sometimes when I try and transfer large files to it such as DVDs etc it will suddenly slow down the transfer rate.

For example, I can sometimes copy over a DVD file in iso format in about 4 minutes or so. Then other times the time will slowly creep up and up to say 10 mins, then up to 180 mins etc.

I then have to reboot the pc and will then be able to transfer at normal speeds again for a while until it starts creeping up again.


Does anyone know why this is happening?

Cheers Ferret

:)
 
We talking normal copy pasting or is it creating an image? If so what program you using & are said discs clean/no scratches/etc? Also, running latest firmware for the drive?
 
I am cutting and pasting large iso files and mkv's from one drive to another, there are no cd/dvds involved.

The Samsung drive has the firmware it came with from Overclockers.

Cheers
 
Antivirus? Which OS? Something might be doing some random indexing malarky. Also check RAM usage when copying. Copying large files can quickly eat up RAM and put your PC into a go slow. Do you have a paging file?
 
I am cutting and pasting large iso files and mkv's from one drive to another, there are no cd/dvds involved
From experience, stopped cutting & pasting (moving) large files after I lost a backup image when the system crashed. Much safer to copy paste, make sure everything is ok then delete the file from original place.

Could be an issue with motherboard chipset drivers. Running the latest?
 
Seems weird that it only happens with one drive though?

If it was antivirus, indexing or chipset drivers etc then wouldnt it happen with all drives?

Cheers

Ferret
 
Hi Op

Your HD problem sounds like either a background OS process is accessing your HD without you being aware of it (disable anti-virus and Windows HD indexing services to check for this) or the HD is pre-fail. It might be worth running some S.M.A.R.T. checks on the HD I would reckon just to check for the latter... Is the drive properly defragmented using a proper tool, like PerfectDisk, and not the feeble excuse for this function bundled with the OS!

It might be useful to use Speedcommander to see what real transfer speeds you are getting. The MS Windows XP explorer.exe GUI is a bit of a joke (you know 'MS time' is not relative to anything in the known universe :D). Speedcommander does have the advantage over explorer in that you can pause large transfers to ensure that multiple transfers are carried out in sequence (with the stacked requests resuming automatically). NCQ doesn't really seem to really help in my experience (but should) and the Windows OS kernel is hopeless (compared to say the 2.6.x Linux kernel) at handling multiple accesses to a single HD (especially multiple writes or a combination of writes and reads). You always seem to end up thrashing the HD - hence my preference for stacking big transfers in SpeedCommander when using Windows XP (32/64-bit).

Bob
 
try turning off superfetch (if using vista) as i find that can really mess with transfer rates as it does not Care if your using the drive at the same times it want to fill your ram up
i found that out when i was burning trans-coded DVD file after the file was trans-coded it started to burn to the dvd but vista thought i be an good time to fill that file into system ram at the same time you do that with HDD = fail speeds was takeing 15 mins to burn that norm take 5 min)

check kernel times as well (task manager performance > view > Show kernel times there should be little Red showing if its 50% on an dual core or 25% on an Quad core you may have an driver problem)
 
try turning off superfetch (if using vista) as i find that can really mess with transfer rates as it does not Care if your using the drive at the same times it want to fill your ram up

I presume OP is using XP as Vista (correctly) shows transfer rates for files in bytes(units of) / second - not some wishy-washy "time remaining" :D Another advantage of "Speed Commander" is that it (correctly) shows transfer rates in bytes(units of) / second!

check kernel times as well (task manager performance > view > Show kernel times there should be little Red showing if its 50% on an dual core or 25% on an Quad core you may have an driver problem)

Process Explorer (freeware utility by Sysinternals - NB MS bought out Sysinternals a couple of years ago) would be far more effective at testing both interrupts and deferred procedure calls. Windows built-in task manager is completely rubbish at telling you anything!! You can even check the I/O rate for individual processes with Process Explorer (as a dynamic graph).

It did also occur to me that OP could use the Performance Monitor tools (under Administrive Tools on the Programs menu). Using System Monitor you can add counters for all kinds of attributes about your physical disks (especially read/write and total transfer rates in bytes) and graph these dynamically...

Trying this Performance Monitor on a laptop with 10x external drives attached. I am saving torrents to 1x HD which quite clearly shows this individual drive as quite active. My other 9x external HDs show as an physical HD R/W activity flatline. Yeh so OP you can test for a rogue process that is accessing your HD. It is quite likely something like this is then thrashing the HD when you initiate a file transfer to/from that drive.

Bob
 
mmmm... I couldn't see any processes eating up cpu but I just noticed when it slows down its going into PIO mode and I also get an error in event viewer

Event ID 51
There was an error detected on ......hardisk1/d during a paging operation.


This only happens when transferring large files, not sure why

Any ideas?
 
Last edited:
Event ID 51
There was an error detected on ......hardisk1/d during a paging operation.
This only happens when transferring large files, not sure why
Any ideas?

Could possibly be a pre-failure condition. Like I said before(!!) you really need to run an extended S.M.A.R.T. diagnostic test on the drive.

Most of the Windows S.M.A.R.T. checking software that I have tried is complete garbage. Your best bet is to download Cygwin and use the native Linux tools (smartmontools)- but compiled for a Windows platform. These tools allow you to not only read the current S.M.A.R.T. attributes for each of your HDs (included ones connected via SATA port-multipliers, etc.) but also to run an extended S.M.A.R.T. diagnostic test on your HD drives individually. This will pickup error conditions and give you feedback on sectors that have been de-mapped due to errors, etc.
Sorry but that may be a bit of a steep (but useful) learning curve - if you are not familiar with Unix - unfortunately!! It is free to use of course though :D

I also tend to use spinrite with HDs that appear to be failing. It is basically a piece of commercial software which runs at a very low (DOS booted) level. It attempts to enhance the polaziriation state of the magnetic bits on the HD surface. It can work wonders for pre-fail drives!! Unfortunately it may struggle to access drives on modern SATA Host Controllers (due to driver issues).

Bob
 
Ok, I've sorted it out. I changed the cable! Must have been faulty

Cheers

Guys

Ferret

Ah good to hear it was something simple! I always stick to high quality latching SATA-2 cables (since they came on the market). I have had some really bad/ annoying experiences with early SATA cables!! So I didn't even think of that one (given it's a distant bad memory for me)... Whoops!! :eek:

Bob
 
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