I've looked through the archives and can't find much.
I've waded through IBM's web sites and can't find specifics...
Has anyone found any recomendations on max number of 3590's (FC attached)
per FC card on host ?
Environments I'm looking at are 7017-S70's that have a max of 4 FC cards
(6227's) per system.
I'm already driving my ESS storage with 2, that would leave me with 2 cards
to drive 8 tape drives.
(or maybe mix everything together and let the device drivers balance the
loads ????)
So is anybody driving 4 3590's off a single FC adapter and if so how are
your data transfer rates look with 1, 2, 3 & all 4 drives running ?????
Math says
1Gb (1024Mb/sec) FC card is 128 MB/sec or 450 GB/hr
100 MB/sec burst data transfer rate of 3590 is 351 GB/hr
so really 1 card per 1 drive but 4 cards could drive 5 drives...
NOW...
With 3590-B1A's & E1A's that are SCSI attached (one drive per one scsi
adapter) I see migrations run at
B1A'a 22-ish GB/hr
E1A's 32-ish GB/hr
Now SCSI attached drives have a burst rate of 40 MB/sec 140 GB/hr
So on my E1A's I see migrations run at 23% of the burst rate
So if I expect the same from FC, migrations across FC would be at 23% of 100
MB/sec or 23% of 351 GB/hr or 80 GB/hr if I have one drive per one FC
card...
So with all that said, a single FC adapter should be able to drive five and
a half (5.5-ish) FC 3590-E1A's or H1A's and run at least as good as SCSI
attached at a one-to-one atachment... right???
Anyone have any thoughts...
(other than I need a vacation)
Dwight E. Cook
Software Application Engineer III
Science Applications International Corporation
509 S. Boston Ave. Suite 220
Tulsa, Oklahoma 74103-4606
Office (918) 732-7109
