Test setting the iSCSI daemon settings for the Target to the following below. When getting better performance - see if we can replace this map with a current one.

Please go to the console and enter crtl + alt + w then select Tuning options then iSCSI
daemon options then Target options then select Target of choice.

maxRecvDataSegmentLen=262144
MaxBurstLength=16776192
Maxxmitdatasegment=262144
maxoutstandingr2t=8
InitialR2T=No
ImmediateData=Yes

Many are reading this thread so we should keep it shorter, but really good job on the comparison!!