Been on unraid 6 beta 10 for quite a while and have an issue with copying large files to my cache drive. For example if I copy a 10gb file over it will pause randomly during the copy for up to 60 seconds, sometimes it will bomb out with a copy error or sometimes it will copy successfully but I would say generally with files over 8gb it will likely fail. My setup is a Phenom II x4 965 @ 3.4ghz with 20gb RAM, with gigabit LAN throughout.

 

Things I have tried:

 

1. Tried smb transfer from wired LAN machines both windows 7 and windows 8.

2. Upgraded to Unraid 6 RC3

3. Moved 256gb cache drive to a PCI Sata card

4. In bios changed SATA from IDE to AHCI

5. Tried to copy to media share and also direct to cache drive with same issue

6. Tried running with no dockers

 

I'm scratching my head a bit with this one and i'm not sure if I can enable SMB logging, also nothing in syslog pertaining to this issue.

 

PS. The issue is purely limited to my cache drive as if I copy direct to an array drive it's absolutely fine. 

One other detail. My SSD cache drive is a 256GB crucial MX100 formatted with BTRFS and my data drives all use XFS.

The root cause seems to have been BTRFS. Scrub kept reporting errors but running a scrub minus -r I still experienced file transfer issues. Since reformatting to XFS all my problems have gone away. No plans for a cache pool so I'm fully in camp XFS.