Help diagnosing random slow backups.

[NJC2]

I've been getting random slowdowns during backups with FFS. The transfer rate will slow to a few KB/sec or completely stop for several minutes. I have an eSATA dock as well as a couple of portable USB drives. It has happened to all of them. It's annoying when it happens, because my weekly backup that usually takes 20-40 minutes, takes 1-2 hours.

When it first happened, I suspected the drive I was using. I ran a full scan with Windows chkdsk, and the manufacturer's diagnostic software, and it was passed both. I found a post on Microsoft's forums and the marked solution was to added each of the drives to Windows' Defender's exclude list. That seemed to do the trick, but that was possibly a coincidence because the problem only went away for a while.

I'm getting these random slowdowns again, and I've noticed some things which makes me believe Windows is the cause, but it only seems to be effecting FFS. When I'm performing a backup using FFS, the transfer rate will drop to just a few KB/sec or even sit at 0KB/sec. The activity light on the PC is solid, but the activity light on the drive itself shows now activity. I can stop the backup and the PC's light stays solid. Using programs such as System Informer, I see no activity on the drives and little to no IO activity at all. Windows Task Manager's Performance tab shows the backup drive's "Active time" at 100%, but shows 0 KB/s transfer rate.

The reason I think Windows is the problem is because it's intermittent, and if I leave the drive on, eventually whatever "activity" is going on stops, and that seems to fix it for a while. When it happens, I can stop FFS and manually copy the files to the drive with Windows Explorer and it's unaffected. Whatever is happening seems to give priority to Explorer, but doesn't give the same priority to FFS file transfers.

This is getting really frustrating, and I'm looking for help to figure it out because it always seems to find the most inconvenient time to do it.

[xCSxXenon]

What antivirus are you using, just Windows Security? Also, disable realtime protection and test again. I know you added it to the exclusion list, try disabling protection anyway. Report back

[NJC2]

Yes I'm just using Windows Security. The previous time it happened, I did disable the real time protection from its settings, as well as stopped the services. I disabled a few other services that I thought might be causing the problem, but that didn't fix it.

[therube]

the transfer rate will drop to just a few KB/sec or even sit at 0KB/sec

I've seen that with crap USB flash drives (TEAM brand in particular).

Though I certainly would not expect that with a eSATA attached HDD (unless that HDD was simply caching data & was taking a really really long time to write it out before accepting more data).

[NJC2]

I'm continuing to see this problem. Since my original post I have built a new PC. Everything is new, including the external dock and my main backup drive. I'm on Windows 11 now instead of 10. I even paid for the supporter edition to try the parallel file copy.

It seems to only bog down when copying large files. It noticed it happen a lot when I'm backing up my Steam directory after certain Steam games are updated, games that use a few, large files. When it gets to those files, it bogs down. I'll stop the backup and temporarily ignore that game's directory, then restart the backup and it goes fine. I then restart the backup to finish that game, and it bogs down again.

I can copy those files through Windows Explorer without any issues.