Hello, I'm having some issues with iSCSI target performance. Recently I made a 1TB ZVOL, mounted it on windows 7 Ultimate (NTFS) with Microsoft's iSCSI initiator. But the performance, in layman's terms, just sucks.
Version is SunOS solaris 5.11 snv_123 i86pc i386 i86pc Athlon64 2800+, 4x500GB SATA2 drives (WD Caviar Green) in raidz, 3GB RAM. Onboard nvidia sata and gigabit ethernet. For the first few seconds Windows file copy dialog shows about 80MB/s, then it starts to slow down to as low as 500KB/s. Tried it with a sparse and non-sparse zvol, quick format. Tried full format on another 10GB iscsi-mounted zvol, but 10 minutes later its still at about 5%. CIFS performance is good, 80MB/s read and 40MB/s write. iperf shows nearly 900MBps throughput. Tried enabling and disabling nagle's algorithm. Also tried linux's open-iscsi on a virtual machine, saw the same performance, really fast at first, then slows down. So, I check with iscsitadm list target, and I see that the backing store is "rdsk" (I used shareiscsi=on). So I manually make a target, using "dsk" (cached?) and i got much better performance. Formatting 10GB was under 10 minutes and writes are about 20-25MB/s. It's still slow but much better than before. So, two questions: 1) Why does the shareiscsi=on option create the target with rdsk if it is much slower? 2) Any suggestions for improving performance? Thanks in advance, Hernan -- This message posted from opensolaris.org _______________________________________________ storage-discuss mailing list storage-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/storage-discuss
