Copy from netw. drive fast, paste to netw. drive slow?

I have my media mirrored on my HTPC and my main rig, and they're directly connected via 1GBit crossover. Therefore I should get maximal HDD read/write speed when transferring. I do when I copy from a mounted network drive, but pasting (either direction) is really slow.

For example, if I paste a 10GB file from 7 to a mounted drive from the XP based HTPC, it takes ~60 minutes. If I jump into logmein and use the HTPC to initiate the copy, it takes <5min (basically the max write of the mounted drive). This difference is in both directions.

I searched but only found "slow network speed" in general, no one seemed to have this issue, or at least realize it was the issue.

Seriously, no one has noticed this?

jemcgarvey said:

XP based HTPC, it takes ~60 minutes.

Thats the problem, XP can only handle 60KB I/Os of a file at a time for network copies because of an SMB 1.0 protocol limit on every operation, XP also has out-of-order I/O problems that can cause Vista/Win7 to drop the I/O down to 32KB under a few circumstances. Vista and Windows 7 are able to scale the amount of KB's per IO however and gain massive transfer speed increases.

Unfortunately, you'll never get good transfer times transferring things to or from an XP box because of its hard-coded I/O limitations.

Steven

Please excuse me, but that is irrelevant information, and also happens to be completely untrue. Please read my post. Transfers in either direction saturate my HDD I/O (~100MB/s between 2TB drives), as long as I initiate the copy from the destination. If I initiate the copy from the "copy from" pc, I usually get less than 15MB/s.

A. The issue is identical both ways, though one is Win7 Pro 64 and the other XP 32 Home
B. There is no "hardcoded XP I/O limit" of 32KB/s, because my "slow speed" is 1000 times that

Thank you for trying to help, but a canned response with false information is not really what I'm looking for...

jemcgarvey said:

Please excuse me, but that is irrelevant information, and also happens to be completely untrue. Please read my post. Transfers in either direction saturate my HDD I/O (~100MB/s between 2TB drives), as long as I initiate the copy from the destination. If I initiate the copy from the "copy from" pc, I usually get less than 15MB/s.

A. The issue is identical both ways, though one is Win7 Pro 64 and the other XP 32 Home
B. There is no "hardcoded XP I/O limit" of 32KB/s, because my "slow speed" is 1000 times that

Thank you for trying to help, but a canned response with false information is not really what I'm looking for...

The problem is both ways because an XP machine is involved here, There is a hardcoded limit, I hope you know who Mark Russinovich is (Windows kernel developer) because if he's lying then I wouldn't know who to believe.

"Prior to Windows Vista, it took the straightforward approach of opening both the source and destination files in cached mode and marching sequentially through the source file reading 64KB (60KB for network copies because of an SMB1.0 protocol limit on individual read sizes)"

"you’ll see the biggest improvements over older versions of Windows when copying files on networks where the SMB2’s I/O pipelining, and Vista’s TCP/IP stack receive-window auto-tuning can literally deliver what would be a ten minute copy on Windows XP or Server 2003 in one minute"

Source: Mark's Blog : Inside Vista SP1 File Copy Improvements

Since I doubt you'll take my advice, I suggest watching this video from Mark and learning how to troubleshoot anything on your system yourself:
Advanced Windows Troubleshooting with Sysinternals Process Monitor

Steven

My apologies, I misinterpreted your 32KB I/O as "32KB/s". I assumed that the problem couldn't be the OS because of it's bi-directionality, but I have some more Win7 keys so I'll see if 7-7 works. Thanks, and sorry for the misguided frustration.