How to achieve over 2 TB/hr network backup with Integrity entry-class servers running HP-UX 11i v3

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Table 2: Summary of configurations recommended for optimal performance
Performance
metric or optimal
configuration
Recommended,
optimal
configuration
Notes
Tuning combination
(buffers and I/O
block size)
32 buffers and
256KB I/O blocks
for LTO-4 tape
devices
The 256KB I/O block size is recommended especially
for systems that have the Online JFS product installed, as
this block size implicitly enables the default setting for
the Direct I/O feature of the file system, which improves
backup performance.
Maximum backup
data I/O throughput
for a client over a
single 1GbE NIC
port
113 MB/s This is also the maximum link speed for a 1GbE port.
These results could be achieved with three concurrent
data streams on the client; however, four concurrent
data streams are recommended to make allowances for
temporary lags in any individual data stream resulting
from small files, disk agent delays, and so forth.
Maximum I/O
throughput rate to
one HP LTO-4 tape
drive
Greater than 240
MB/s, with four
data streams
optimal from each
of two clients
This assumes 2:1 compression. The more compressible
the data, the higher is the I/O throughput rate to the
tape media. HP’s exclusive Data Rate Matching feature
optimizes performance by matching the host system I/O
data speed to keep the drives streaming consistently.
Optimal number of
HP LTO-4 tape
devices per 4Gb FC
port
No more than 2
per 4Gb FC port
A 4Gb FC port can achieve approximately 410 MB/s
I/O throughput. Two LTO-4 tape devices on one 4Gb
FC port consumes about 334 MB/s of bandwidth, not
leaving additional bandwidth for scaling of another LTO-
4 tape device to run at optimal throughput.
Client hardware
configuration for
optimal backup
performance
Minimum of 2
CPUs and 4 GB of
memory
Tests used a 1GbE port. The amount of client memory
affects performance most significantly, much more than
the amount of CPU available and the type of storage
interconnect. Client backup performance can be
increased using HP-UX 11i v3 tuning features.
Client hardware
configuration for
optimal restore
performance
Minimum of 2
CPUs and 4 GB of
memory
The amount of client memory affects performance most
significantly. The main limiting factor is writing out
restored data to storage through the file system. Client
restore performance can be increased using HP-UX 11i
v3 tuning features.
General considerations and best practices
o Numerous features provided by HP-UX 11i v3 help optimize and monitor backup and restore
performance, including:
 Display I/O throughput for tape devices (sar -t)
 Display of all paths to a specific device (ioscan -m lun)
 Display I/O throughput for I/O ports (sar -H) to view I/O spread across all HBA
ports
 Set specific I/O path for tape devices (scsimgr set_attr -a lpt_to_lockdown)