Heya all, I am using OSC git tgt tree for testing iSER with virtualization. My research focus in on I/O performance in virtualization tehniques (OpenVZ, VMWare server, Xen).
I am using CentOS5 + OFED1.2.5 where it is possible (on target and OpenVZ) with Dell 1950 servers with 4GB ram with Mellanox single port memfree infiniband cards. On target node i usually setup my iSCSI target like this: dd if=/dev/zero bs=1k count=1 seek=1048575 of=/dev/shm/tid1lun1 ./tgtadm --lld iscsi --mode target --op new --tid 1 --targetname node1.nejc.net ./tgtadm --lld iscsi --mode target --op bind --tid 1 --initiator-address ALL ./tgtadm --lld iscsi --mode logicalunit --op new --tid 1 --lun 1 --backing-store /dev/shm/tid1lun1 And the performance from client using ib_iser, measured with disktest, is around 1030MB/s which is quite impressive. But the performance drops significantly when I increase the backing store size to 3.5GB. Usually I get around 400MB/s. This happens with tmpfs or with /dev/ram0. Could you tell me what is the reason for that? Maybe internal kernel stuff or anything else. My init scripts on target and client are available here: http://www.nejc.net/diploma/tgtd/ Thanks for developing such great software again... cheers, Jernej _______________________________________________ Stgt-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/stgt-devel
