HP StorageWorks 2/16V HP StorageWorks Fabric OS 5.3.x administrator guide (569 - Page 392

FCIP fastwrite and tape pipelining, Table 99 Using fastwrite and tape pipelining (continued)

Page 392 highlights

FCIP fastwrite and tape pipelining When the FCIP link is the slowest part of the network and it affects speed, consider using fastwrite and tape write acceleration, called "tape pipelining." Supported only in Fabric OS 5.2.x and higher, fastwrite and tape pipelining are two features that provide accelerated speeds to FCIP tunnels in some configurations: • Fastwrite accelerates the SCSI write I/Os over FCIP. • Tape pipelining accelerates SCSI write I/Os to sequential devices (such as tape drives) over FCIP, which reduces the number of round-trip times needed to complete the I/O over the IP network and speeds up the process. In order to use tape pipelining, you must enable fastwrite as well. • Both sides of an FCIP tunnel must have matching configurations for these features to work. Unlike IPSec, compression, fastwrite, and tape pipelining features do not require any predefined configurations. This makes it possible to enable these features by adding optional parameters such as -c, -f, or -t when you create FCIP tunnels. Enabling fastwrite and tape pipelining Fastwrite and tape pipelining require no parameters. Both features are enabled by turning them on during the tunnel creation process. They are enabled on a per-FCIP tunnel basis. See "Configuring FCIP tunnels" on page 411 for details. Constraints for Fastwrite and Tape Pipelining Consider the constraints described in Table 99 when configuring tunnels to use either of these features. Table 99 Using fastwrite and tape pipelining Fastwrite Tape pipelining Each GbE port supports up to 2048 simultaneous accelerated exchanges, which means a total of 2048 simultaneous exchanges combined for fastwrite and tape pipelining. Does not affect FICON traffic Does not support multiple equal-cost path configurations (see "Supported configurations" on page 409). Each GbE port supports up to 2048 simultaneous accelerated exchanges, which means a total of 2048 simultaneous exchanges combined for fastwrite and tape pipelining. Does not affect FICON traffic Does not support multiple equal-cost path configurations or multiple non-equal-cost path configurations (see "Supported configurations" on page 409). 398 Configuring and monitoring FCIP tunneling

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398
Configuring and monitoring FCIP tunneling
FCIP fastwrite and tape pipelining
When the FCIP link is the slowest part of the network and it affects speed, consider using fastwrite and
tape write acceleration, called “tape pipelining.” Supported only in Fabric OS 5.2.x and higher, fastwrite
and tape pipelining are two features that provide accelerated speeds to FCIP tunnels in some
configurations:
Fastwrite accelerates the SCSI write I/Os over FCIP.
Tape pipelining accelerates SCSI write I/Os to sequential devices (such as tape drives) over FCIP, which
reduces the number of round-trip times needed to complete the I/O over the IP network and speeds up
the process. In order to use tape pipelining, you must enable fastwrite as well.
Both sides of an FCIP tunnel must have matching configurations for these features to work.
Unlike IPSec, compression, fastwrite, and tape pipelining features do not require any predefined
configurations. This makes it possible to enable these features by adding optional parameters such as
–c
,
-f
, or
-t
when you create FCIP tunnels.
Enabling fastwrite and tape pipelining
Fastwrite and tape pipelining require no parameters. Both features are enabled by turning them on during
the tunnel creation process. They are enabled on a per-FCIP tunnel basis. See ”
Configuring FCIP tunnels
on page411 for details.
Constraints for Fastwrite and Tape Pipelining
Consider the constraints described in
Table 99
when configuring tunnels to use either of these features.
Table 99
Using fastwrite and tape pipelining
Fastwrite
Tape pipelining
Each GbE port supports up to 2048
simultaneous accelerated exchanges, which
means
a total of 2048 simultaneous
exchanges combined
for fastwrite and tape
pipelining.
Each GbE port supports up to 2048
simultaneous accelerated exchanges, which
means
a total of 2048 simultaneous
exchanges combined
for fastwrite and tape
pipelining.
Does not affect FICON traffic
Does not affect FICON traffic
Does not support multiple equal-cost path
configurations (see ”
Supported
configurations
” on page 409).
Does not support multiple equal-cost path
configurations or multiple non-equal-cost path
configurations (see ”
Supported
configurations
” on page 409).