[Samba] copy files and it would NOT copy everything

[lejeczek]

hi everybody

I'm dealing here with a very very bizarre situation:
on a Win7 I copy larger sets of data, between 10 and 30GB 
(~20K of files in 2.5K folders)  everything starts very 
normal, I select all the data, copy & paste.
Copying begins and I see progress bar moving normally 
towards the finish and it finishes - no errors no messages - 
yes most of data does not get to the target folder.

source and target are on separate shares (copy everything 
from one share to another) which respectively are on 
separate storages - but it's all one samba on one host (RHEL 
6.5)
source (read-only) is a traditional HDD => ext4 
(rw,noatime,nodiratime,barrier=0,usrjquota=aquota.user,grpjquota=aquota.group,jqfmt=vfsv0)
target is a LVM's LV raid 0 (two SSDs) => xfs 
(rw,noatime,nodiratime,quota,pquota,nobarrier,discard)

samba 3.6.9-168.el6_5
2.6.39-400.214.5.el6uek.x86_64

any any ideas? greatly! apreciated
regards
P.