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Data Transfer Rate

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July 14, 2008 3:02:32 PM

I have yet to understand how transfer rates go.For example sata150 supports transfers up to 1500mbits ~ 185MB/s which means that if you copy a 350mb file it will take approximately 2-3 secs.

Well i have a sata150 seagate drive and i tried copying a file of such size in the same directory with a different name,and the transfer dialog popped up and the estimation was 2 minutes?

Well it's either 185MB/s my a** or I'm not getting the point of what that means.

So which is it,so i can finally clear this issue I'm having.

More about : data transfer rate

a b G Storage
July 14, 2008 3:20:27 PM

while the maximum transfer rate for SATA is 185MB/s, the seagate drive is only going to use up about 40MB/s of that. A 10,000rpm drive will use about 80MB/s to 120MB/s. Basically the sata bus speed does not equal operational speed, it just defines the MAXIMUM operational speed.
July 14, 2008 3:44:22 PM

Well I assumed this was true but seriously from a theoretical 2-3 sec transfer to a 2 minutes transfer?I mean really?

What's the quickest and most flexible way to move files around from drive to drive including network drive?

What equipment and setup have I got to go into,to achieve maximum operation of file transfers and file maintenance?
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July 14, 2008 4:23:12 PM

therock003 said:
Well I assumed this was true but seriously from a theoretical 2-3 sec transfer to a 2 minutes transfer?I mean really?

What's the quickest and most flexible way to move files around from drive to drive including network drive?

What equipment and setup have I got to go into,to achieve maximum operation of file transfers and file maintenance?
You have just learned the big SATA lie. It is the theoretical throughput, the actual throughput is dictated by the physical properties of the drive itself. By the way "SATA I" is really SATA 1.5Gb/sec. and "SATA II" is really SATA 3Gb/sec. You will see an increase in read/write speed of the drive buffer but not to the theoretical bandwidth and the buffers are still relatively small.

If you want the fastest drive then look at 3.5" Hard Drive Charts or Enterprise Hard Drive Charts. Not all the new drives are in the list so use it as a guide only. Enterprise drives are optimized differently than desktop drives. You need to consider all of the parameters not just read/write times i.e., random access time etc., depending on your use. For big files you will probably want one of the 750MB - 1TB drives with PMR.
a b G Storage
July 14, 2008 8:13:40 PM

therock003 said:
Well I assumed this was true but seriously from a theoretical 2-3 sec transfer to a 2 minutes transfer?I mean really?

What's the quickest and most flexible way to move files around from drive to drive including network drive?

What equipment and setup have I got to go into,to achieve maximum operation of file transfers and file maintenance?


If the file is just a single large file, it should still be able to sustain 60+ MB/s, and complete the transfer in a matter of seconds. What really slows them down is when there are a whole lot of small files that need to be placed in various locations across the disk - this can drop data rates to a tiny fraction of the sequential rates.

July 15, 2008 8:48:54 AM

Dunno man what the hell is happening but i did some timings.

Single 175mb file Results
---------------------------

One copy of the file->6 secs(175/6~30 MB/s)
Two copies of the file->7 secs (350~50 MB/s)Yeah strangely enough it took one more second to copy two copies of this file on the same folder.

Run this test multiple times.

And a test at a single 700 MB file
----------------------------------

One copy of it 30 secs
Two copies of it 1 min 15 secs. I guess this time it wasn't below half as much.but more than half as much.

So it seems the best I've got is 50 MB/s but throughput is 30 MB/s and considering i have a seagate 7200.10 connected on sata1 well that makes me kinda mad.
July 15, 2008 9:25:04 AM

There are many factors to consider besides the maximum xfer rate of your controller. File fragmention is one.

And your 7200.10 drive was good in its time, but lacks cache and a decent controller.
July 15, 2008 9:51:56 AM

One major thing to consider is, I've found, that some hard drives slow down noticably when jumpered to operate as a SATA-150 drive.
Tried it with two 7200.11 750-GB drives, and two WD Caviar SE16 160-GB drives on 3 different Asus motherboards (A7N8XE-Deluxe, P5K-E, and a P5E).

And I'm not just talking about a little slower, they were all in the neighborhood of how slow your drives are working now.

The older Asus was limited to a SATA-150 bus, and the other 2 boards are SATA-300.

As soon as I jumpered the 7200.11's to SATA-150 compatibility, transfer rates dropped to about 35-MB/sec. (averaged transfer rate) on all motherboards.
Un-jumpered and running as SATA-300 drives (on the 2 newer motherboards) the transfer rate jumped up to where it should be (averaging >80-MB/sec)
The same results were had when I did it to the WD Caviar drives (SATA-300 speeds averaged 65-MB/sec, SATA-150 speeds averaged a little over 30-MB/sec)
So, data transfer speeds, on some motherboards (or at least using particular chipsets) is impacted negatively by being jumpered to be compatible with SATA-150.

But it's not a bus limitation: it's either the chipset, the hard drives (they are somehow being crippled by the SATA-150 jumper), or a combination of both.

Anyone else see this happen, or am I just high & farout, man?
July 15, 2008 10:33:28 AM

So guys what do you think?Though i couldn't perform a write test.Some message about removing partitions when i had none!.Anyway Screen follows.

July 15, 2008 10:36:20 AM

I installed one jumpered for a customer but it was on a dell so I never checked. I have a Raptor which is 150Gb/sec and it runs at 83.4MB/sec. Of course it's not strapped. I suspect something with the drive itself, but I don't know for sure.
July 15, 2008 10:37:58 AM

therock003, you have major problems. Check for PIO instead of DMA on the controller in Device manager.

Although CPU usage should be higher under PIO, and the drive shouldn't be that slow.
July 15, 2008 11:03:24 AM

But it's a sata drive,i thought PIO/DMA are for IDE controllers.Anyway i checked device manager and i didn't see any option displayed and scsi/raid host controllers for such an option.
July 15, 2008 11:13:20 AM

Do you have the drive set as SATA / AHCI in BIOS or IDE/Native. You have a serious problem with your drive read speed. Check the health tab in HD tune. Additionally, post all of your specs. including the OS. New rig? New drive?
July 15, 2008 11:21:21 AM

You should be getting somewhere around 60MB/sec average read speed and you are getting 4.4MB/sec. Big problem, get it?

Look Under all Primary and secondary IDE Channels, see the screen shot. What SATA port is it plugged into? Specs please.

July 15, 2008 11:40:06 AM

Quote:
Do you have the drive set as SATA / AHCI in BIOS or IDE/Native.


I'm not sure,dont quite understand what that means,but other than that i do get that read speeds are low,but why?

I dont think my sata drive is registered on the IDE controller.Everything is not applicable except Primary Channel Device 0 which is set to DMA if available and result is Ultra DMA 4,but this is my IDE DVD Plextor recorder I guess.

Other than that.I first boot this computer around Nov-December 2007.

SPECS:
Athlon 64 3700+San Diego @2.25 2GB DDR-1 Windows server 2k3 R2 SP2.
July 15, 2008 12:00:01 PM

What motherboard? This is one you built or is it a Dell or something?
July 15, 2008 12:27:05 PM

Abit ax8 v2.0.

I set it up.Maybe it's a defragmenting issue.I've used diskperfekt but it doesnt seem to have improved.I will proceed with further defragmentations.
July 15, 2008 12:38:20 PM

I don't think your drive could be that fragmented, you have a bigger problem.
July 15, 2008 12:59:23 PM

No i narrowed it down.Running firefox with the whole lot of the addons i've installed somehow produces crazy results and pc is behaving out of the ordinary.

New screenshot with firefox terminated.Firefox screwes up my system big time.

July 15, 2008 1:18:55 PM

Those numbers are good.

Lucky, because there is no manual available for that mobo and I never would have figured that it was Firefox, with or without a manual. I never would have gotten enough info.

I've never heard of Firefox causing anything remotely like that before, ever.

I would disable the addons and see if the speed remains good. If so, enable them one at a time until you find the culprit.

If the speed is still bad with the addons disabled then delete them and check the speed. If you have to delete FF and reload.
July 15, 2008 1:36:10 PM

I have like 78 addons installed.I have disabled like 10 of them but most of them are useful to me.What i do is momentarily terminate firefox and re launch it when needed.

But i make such a gruesome use of firefox that it downs my system to its knees.

By the way what's the burst rate and y is it so high?
a b G Storage
July 15, 2008 3:57:54 PM

It's the data rate for a small file that is in the hard drive's cache. It's high because the cache is RAM, so it is much faster than coming off the disk.
July 15, 2008 8:49:24 PM

If you look at the 4.4MB HDtune you will notice that your CPU usage is only 13%. I wouldn't call that bringing your system to it's knees, at least by the CPU usage. I ran HD Tune with Prime95 running and it showed CPU usage correctly at 100%. So FF is bringing something in your system to it's knees but not the CPU.

I've never heard of anyone using 78 addons, but there's always a first time. I still suspect that it's one, or a few, addons that are causing this. You will have to do the leg work to determine if it's a few or a lot of addons that are causing the slow down.

Good luck.
a b G Storage
July 15, 2008 9:09:53 PM

My best bet would be that something (likely the addons) is trying to access the hard drive continuously at the same time that HDtune is. This conflict of multiple things accessing the drive at once causes the horrendous speed. Try disabling the addons and see if your speed improves.
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