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eSATA coyping files at 6MBs per second???


I am copying files with from a laptop over to the external harddrive using eSATA connection.

I understand that the lowest speed for SATA is 1.5Gb/sec. Which translates to 187 MBs / sec. But the copy speed over to the hard drive is 6MBs / sec.

Any ideas on what could cause such slowness?

I disabled Mcafee Scan and saw no improvement.

4 Solutions
Throughput is a function of block size. iT is also decreased by latency.   6MB/sec could very well be accurate.

When you copy files, you are not just copying sequential data.  Every time you copy a file you copy much more then the file itself, you have to move the head to the place on the disk that has directory information, and have to teach it where the new file is.  then if there is not enough free area, the heads have to go somewhere else to see where the rest of the file can be put.

When a file is accessed, it has to update both the source and destination disk drives and then find out where the file is and update those counters.

If you want more speed, i would do following
 - defrag  both source and destination.
 - look at performance monitor, and see if any tasks are running that can slow things down, perhaps your laptop needs more memory and bottleneck is the SOURCE, not destination?
 - reformat the destination drive and make the NTFS chunk size be 64KB instead of default 4KB.  This will make a huge improvement, as it will copy 64KB at a time.   (But the bottleneck will still be the source disk).

Download one of a zillion different benchmark programs and do a benchmark on the target disk. YOu could very well see 100MB/sec with 256KB sequential raw reads/writes.  This will prove that there is no physical problem.

(If you do have lots of errors like unrecoverable read errors on the external drive, or even source drive, then they can certainly account for a huge performance hit, so benchmarking also insures that one of the HDDs isn't throwing errors and about to die)
Raymond PengSystems EngineerCommented:
Make sure you don't have a SSD  -- You DO NOT want to defrag that.
It is an urban myth that you can't / shouldn't defrag a SSD.  (But it is likely going to be a waste of time, because latency on the better ones is measured in microseconds, rather then milliseconds, so defragging is rather  pointless)

Think about it .. how is a SSD going to tell the difference between defragging, and moving your itunes folder somewhere else, or zipping up a few files?  

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nvs_victorAuthor Commented:
Thanks guys.

@ dlethe
However, when I used a USB cable to transfer the data from the external hard drive to the second computer, it hit 60MBs/ sec. It can't be the hard disk. Maybe it was the first computer being slow...

@ shahzoor
Thanks! I'll take a look at it.

Just wanted to find out what your thoughts are on a slow eSata.
No way can you get 60MB/sec on USB, unless it is all USB 3.0

The standard USB 2.0 simply can't move data that quickly.
nvs_victorAuthor Commented:
I'll double check.
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