MT - Maximum CPU Time

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# MT - Maximum CPU Time

This Natural profile and session parameter determines the maximum amount of CPU time which can be used by a Natural program.

Important
In server environments where the server itself runs without any operating system controlled CPU time limit, it is strongly recommended to set the profile parameter `MT` to a non-zero value to prevent the formation of endless loops caused e.g. by application errors. This recommendation applies to Natural RPC and Natural Development Server servers.

Possible settings | `1 - 9999999` | Maximum amount of CPU time in seconds. Notes: If Natural Security is installed, the profile parameter `MT` can be overridden within Natural Security. With Natural Security, the maximum value for the profile parameter `MT` is `32767`. To use a higher value as specified with the `MT` profile or session parameter, specify `MT=0` within Natural Security.
`0` | `MT=0` defines that no Natural CPU time limit is to be in effect.
Default setting | `60` |
Dynamic specification | yes |
Specification within session | yes |
Applicable statements | `SET GLOBALS` |
Applicable command | `GLOBALS` |
Application programming interface | `USR1005N` | See SYSEXT - Natural Application Programming Interfaces in the Utilities documentation.

Notes:

1. This Natural profile and session parameter only applies to programs executed in batch mode, under Natural Development Server (SPoD) or under Natural for TSO.applies only to mapped z/OS environments (SPoD).
2. This Natural profile and session parameter applies only to mapped z/OS environments (SPoD).
3. CPU time measurement starts when a Natural program is started from `NEXT` mode or by means of a `FETCH` statement, that is, on program level 1. In non-batch mode (Natural Development Server, Natural for TSO), CPU time measurement is restarted at every terminal I/O.
4. The limit for programs operating in interactive mode is controlled by the TP monitor in use.
5. The maximum value that can be used is determined by the operating system environment. Any setting in excess of the maximum is reduced to the maximum supported by the operating system.
6. In system environments which do not support CPU time measurement, the limit is interpreted as elapsed time. The CPU time limit is ignored for systems without timer support.
7. Within a Natural session, the `MT` profile parameter can be overridden by the session parameter `MT`.
8. When running zIIP-enabled under z/OS, the `MT` profile parameter applies separately to both TCB (except under CICS) and SRB (zIIP) processing modes. If `MT=0` is set in SRB mode, Natural uses the existing z/OS TCB time limit to avoid endless loops because there is no z/OS CPU time limit (for example, the JCL TIME parameter) for SRBs.
9. The `MT` parameter is supported under CICS SRBs (zIIP), but not under CICS TCBs. If `MT=0` is set, Natural uses the CICS runaway time as CPU time limit in SRB mode. A CPU timeout abend that occurs when a CICS open TCB is used cannot be recovered. It causes an immediate AICA abend of the CICS task and the Natural session is aborted.