istgt write errors

[David Newman]

On an 8.0-RELEASE/amd64 box, I used the net/istgt port to share iSCSI
targets. The installation succeeded, but I'm now seeing write errors
when using the targets:

Mar 16 15:10:26 bettini istgt[1202]: istgt_iscsi.c:
640:istgt_iscsi_write_pdu: ***ERROR*** iscsi_write() failed (errno=32)
Mar 16 15:10:2	6 bettini istgt[1202]:
istgt_iscsi.c:3038:istgt_iscsi_op_scsi: ***ERROR*** iscsi_write_pdu() failed
Mar 16 15:10:26 bettini istgt[1202]:
istgt_iscsi.c:3859:istgt_iscsi_execute: ***ERROR*** iscsi_op_scsi() failed
Mar 16 15:10:26 bettini istgt[1202]: istgt_iscsi.c:4337:worker:
***ERROR*** iscsi_execute() failed
Mar 16 15:10:30 bettini istgt[1202]: Login from 172.31.4.12
(172.31.4.22) on iqn.2010-04.com.example.bettini:bettini4 LU5
(172.31.4.5:3260,1), ISID=23d000001, TSIH=4, CID=0, HeaderDigest=off,
DataDigest=off
Mar 16 15:12:10 bettini istgt[1202]: ABORT_TASK
Mar 16 15:14:15 bettini istgt[1202]: ABORT_TASK
Mar 16 15:16:04 bettini last message repeated 2 times

The istgt documentation doesn't offer any help in pinpointing a root
cause for the write errors.

Writes to these targets are extremely slow, too. In case it matters, the
target is a ZFS block device set up with 'zfs create -V 1T tank/bettini4'.

Thanks in advance for clues on the care and feeding of iSCSI on 8.0-RELEASE.

dn