SERVSIZE parameter

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Maximum size of this server

Summary

Default value
65536 as of version 7.7 (and zap maintenance in 7.6, 7.5, and 7.4); formerly, 0
0 as of version 7.9
Parameter type
Server
Where set
View only; set on first NSERVS user's parameter lines
Related products
All
Introduced
Model 204 V2.1 or earlier

Description

The size of the server area to be allocated, rounded up to a multiple of the smallest operating system page size. So, for example, an Online with servers set to 750000 will show 753664 (the next highest multiple of the 4096 page size) under z/OS.

Under 7.9, if the entire server is placed above the bar using SERVGA and/or SERVNSA, this parameter should be omitted (or set to zero) in order to avoid below the bar allocation.

SERVSIZE must not be a negative number. If the default value is used, the server area allocated is exactly large enough to contain the tables for the user specified on the same parameter line. If a positive value less than FIXSIZE (user's fixed size) is specified, Model 204 increases the value so that the server area allocated is large enough to hold the user's fixed size.

In a Model 204 run that uses server swapping (the typical case for Online runs), the size of each server is likely to be limited by the physical device used for swapping.

  • When a CKD device is used for swapping, server size is limited to the device's cylinder size.
  • When an FBA device is used, server size is limited by the amount of virtual memory available to Model 204.
  • All servers defined for the run, along with many other blocks of storage, must fit in virtual memory.
  • In a run that does not use server swapping (the typical case for batch runs), the servers for all users in the run must fit in virtual memory.

For a description of how the sizes of the fixed table and the variable table are calculated, see Sizing user server areas.

Handling SQL statements greater than 32K bytes

When handling an SQL statement that is greater than 32K, you must consider the SERVSIZE parameter: If its value is not large enough, the error message invoked includes the name of the relevant parameter whose value needs to be increased (LSTBL, LNTBL, etc.).