Moving Data
From PCI-X Bus – 133Mhz 64 bits = 1064 MB/s
– Throughput
• FC HBA 1 Gb/s 100 MB/s
• FC HBA 2 Gb/s 200 MB/s
• FC HBA 4 Gb/s 400 MB/s
• FC HBA 8 Gb/s 800 MB/s
• JBOD 1 Gb/s FC Disk Drive 90 MB/s
• SCSI Ultra 160 Disk Drive 160 MB/s
• LTO-4 Ultrium Tape drive 130 MB/s
• Tape Library (8x LTO-3 drives) 1280 MB/s
• Disk Subsystem (8x 2 Gb/s ports) 1600 MB/s
Maximum burst values
These are maximum burst values. Although Fibre Channel is designed to
sustain maximum throughput, very few devices can sustain transfers at these
data rates.
The PCI-X bus for instance is half duplex and because of other bottlenecks in
the system, cannot sustain these values.
A FC Direct Attach disk drive in a JBOD can only sustain 90MB/s from the
cache during a read operation for a short time, then it must move the heads
and seek to another track to read more data.
An LTO-3 Ultrium Tape Drive can stream raw data at a maximum 80MB/s.
However, in some applications, with 2:1 compression this can support up to
160MB/s.
A disk subsystem, with 8x 2Gb/s ports can theoretically sustain 1600MB/s
provided it can source data fast enough from the disks on the back end.