The z/OS® operating system assigns an address space ID (ASID) when it creates each address space. However, a limited number of ASIDs are available for the operating system to assign. When all ASIDs are assigned to existing address spaces, the operating system is unable to start a new address space. In this situation, the operating system issues the IEA602I ADDRESS SPACE CREATE FAILED message.
In some scenarios, address spaces that use cross-memory services prevent their ASIDs from being reused and increase the possibility of an ASID shortage. One solution, which became available in Version 1.9 of the z/OS operating system, is to explicitly indicate that specific address spaces can use reusable ASIDs. This article describes the use of reusable ASIDs by WebSphere® Application Server on the z/OS operating system.
The reusable ASID feature is activated on a particular z/OS system when you specify REUSASID(YES) in PARMLIB member DIAGxx. If you do not specify this parameter, the reusable ASID feature is not used. If you are using Version 1.9 of the z/OS operating system, you must apply the Workload Manager (WLM) APAR OA28528.
All code that is running in reusable address spaces, such as MVS exits, must comply with the ASID reuse rules that are outlined in the z/OS Extended Addressability Guide. Otherwise, problems that are like the one described in OA28528 might abend the address space.
START STC1,REUSASID=YES
Avoid specifying the REUSASID option for started tasks that do not use cross-memory services. This approach is not recommended because reusable ASIDs form a separate pool that is not available for reassignment to an ordinary address space.
START BBO6ACR,JOBNAME=BBOS001,ENV=BBOBASE.BBONODE.BBOS001,REUSAID=YES START BBO6DMN,JOBNAME=BBODMNC,ENV=BBOCELL.CFCIMGWI.WITIMGWI,REUSASID=YES
WebSphere Application Server address spaces also can be issued by WebSphere Application Server itself. For example, the address spaces might be issued when the location service daemon starts automatically or when a server starts with the startServer command. In these cases, the daemon or server configuration settings determine whether the REUSASID=YES option is specified on the START command that is submitted by WebSphere Application Server.
Internally-issued START commands
for the daemon always include the REUSASID=YES option.
After you apply this fix pack, new servers have the REUSASID=YES option
on internally-issued START commands. Servers that
are created before the application of this fix pack do not have this
option on the internally-issued START commands.
To change this behavior, manually update the process definitions for
the controller by using either the wsadmin command or scripting to
remove or include the REUSASID option on the server START command.
Also, you can use the updateZOSStartArgs script to add or remove the REUSASID=YES option
for particular servers.
For more information about reusable address spaces, see the z/OS manual MVS Programming: Extended Addressability Guide.