IOMeter source for linux downloaded from the
iometer-devel files on sourceforge.
Only GUI on Windows, with Dynamo on Linux x86_64 Dual
AMD Opteron with Open iSCSI initiator or other iSCSI
initiators, using a LUN from a Chelsio iSCSI Target
1Gig size ramdisk LUN,
with 2 10Gig Chelsio fiber cards back to back, one
running the iSCSI initiator, one running the iSCSI target.
The dynamo starts sending data for about 20-30 seconds,
and then stops sending data, and the performance
numbers shown in the GUI jump by about 2x to 3x the
earlier real numbers.
The fact that data is not being sent is verified by
there being no activity on the 10Gig back-to-back link,
and through iostat and top not showing any cpu usage
for the iscsi initiator and target.
Dynamo does not trip in this way with regular scsi /
sata / sas / raid devices and continues doing io to them.
Most probably Dynamo is not handling the very small
/low latencies with the RAMDISK.
There are no other issues with the setup, because other
linux utilities can access the same LUN, through the
same iscsi and tcp connection, after Dynamo has stopped
sending data to it. (utils like fdisk / mkfs, other io
tools, and the activity on the link is there for those).
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