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[fordem]

The way I explain it is that the disk transfer is like a chain ...

You start with a file on a disk, and read that file, then you transfer the data through the disk interface, through the computers expansion bus, through a network interface, across a network, through a second network interface, across a second expansion bus, through a second disk interface, and finally write the file to the second disk.

The maximum throughput is limited to that of the slowest channel in the chain - things like network drivers can have an inexplicable impact on throughput - I've seen Realtek gigabit NICs max out at 70 mbps (that is not a typo) when used with a generic Microsoft provided driver.

The same no doubt goes for disk controller drivers, but how often do we pay attention to those?

[gunrunnerjohn]

Well, I suspect we can agree that the SATA disks or the DNS-323 is not the cause ot 7byte/sec transfers on a gigibit link.  As far as the system at the other end, obviously, a serious bottleneck there can be a problem.  Truthfully, I have never seen an example as egregious as you state, although I have seen gigabit NIC's and drivers that don't come close to delivering the performance you'd expect.

[fordem]

Hold on a sec - maybe you want try some "small file" tests - and be warned, the results are not going to be pretty.

I've used Microsoft's SyncToy to "back up" several gigabytes of mixed files, including a few thousand html pages - average size 36KBytes - throughput drops to something in the region of 0.5KByte/sec, and the limiting factor IS the DNS-323.

[gunrunnerjohn]

Well, I don't have enough small files like that to do a meaningful test, but if you really want to stack the deck to prove a point, it's always possible.

I made the mistake of thinking we were talking about the tests performed and reported on in this thread.  In case you forgot...

Two file sizes where tested. 150 MB file and a 1,2 GB file.
Made two to three transfers and too the average sped

I don't see any tiny files there, so I'm still not buying your arguments.

[fordem]

I wasn't stacking the deck - back up (using SyncToy and other utilities) has been the primary function of my DNS-323 - the data just happens to be some 14GBytes worth of html pages.

When you have a "system" capable of transferring data from Disk_A in Device_A to Disk_B in Device_B at speeds exceeding 30MBytes/sec in a repeatable test, and "real world throughput" is to the order of 0.5KBytes/sec, some of us wonder why, and some of us investigate.

It also really doesn't matter whether you "buy" my arguements or not - I'm not argueing, just offering suggestions to explain the phenomenon you find curious - feel free to ignore me - you will, if your pursue it, eventually arrive at conclusions very similar to those I have arrived at, I've just had a few years headstart on you.

[gunrunnerjohn]

Again, we were addressing the scenario presented in this thread, you're dragging in a red herring that has nothing to do with the benchmarks provided in the thread.

Do you have anything constructive to add about this person's issue with performance?  Let's forget about your zillions of little files and address the scenario here.

[fordem]

Perhaps you want to reread the thread in it's entirety ...

I'm the thread starter and posted the perfomance degradation I observed using ext2 & ext3 formatted disks - Geraner did likewise - the only person who has expressed any questions on performance was you, hence my offering you a potential explanation.

[gunrunnerjohn]

Well, you're right, I didn't realize that the other guy jumped in the middle, sorry.

Since I have no performance issue, and don't expect tons of tiny files to transfer at the same speed as large transfers, I'll just exit through the left hand door.

[fordem]

You may not, I certainly don't, but you'd be surprised at how many less experienced people do - which is why I took the trouble to point it out.