Maximum-Lus - Cisco 11.0 BT Release Notes

maximum-lus

maximum-lus
Use the maximum-lus TN3270 configuration command to limit the number of LU control blocks
that will be allocated for TN3270 server use. Use the no form of this command to restore the default
value.
Syntax Description
number
Default
Because of the license structure, the default is 2100, which represents the limit of a typical license
(2000) plus a 5 percent buffer. If you configure a value greater than the default, a license reminder
is displayed.
Command Mode
TN3270 configuration
Usage Guidelines
Although the value may be varied at any time, reducing it below the current number of LU control
blocks will not release those blocks until a PU is inactivated by DACTPU or by using the no pu
command.
If the number of LUs in use reaches 94 percent of the current setting of maximum-lus, a warning
message is displayed on the console. To prevent constant warning displays, the threshold for
generating such messages is raised for a period.
The TN3270 server attempts to allocate one LU control block for each LU activated by the hosts. In
the case of dynamic definition of dependent LU (DDDLU) the control block is allocated when the
client requests the LU, in anticipation of an ACTLU from the SSCP host.
By limiting the number of LU control blocks allocated, you can make sure enough memory is
available to support other CIP functions. The control blocks themselves take about 1 K bytes per LU.
During session activity, a further 2 K per LU may be needed for data. On a CIP, 32 MB of memory
will support 4000 LUs. To support more than 4000 LUs, we recommend 64 MB of memory.
Example
The following command allows 5000 LU control blocks to be allocated:
Related Command
pu
30 TN3270 Server Commands
maximum-lus number
no maximum-lus
maximum-lus 5000
Maximum number of LU control blocks allowed. The
allowed range is 0 to 32000. However, the practical upper
limit for concurrently operating TN3270 sessions depends
on the hardware and usage characteristics. The default is
2100.