SHMVIRT_ALLOCSEG configuration parameter

Use the SHMVIRT_ALLOCSEG configuration parameter to specify a threshold at which Informix® should allocate a new shared memory segment and the level of the event alarm activated if the server cannot allocate the new memory segment.

onconfig.std value
A numeric value optionally followed by a comma and another numeric value.
threshold = A number that indicates when the database server should add a shared memory segment:
  • 0 = Default. The database server allocated shared memory segments when needed.
  • .40 - .99 = The percentage of memory used before a segment is added.
  • 256 - 10000000 = The number of kilobytes remaining before a segment is added.

alarm_level: Optional. An integer value from 1 to 5 that specifies the level of the event alarm to raise: 1 = Not noteworthy, 2 = Information, 3 = Attention (Default), 4 = Emergency, 5 = Fatal. The event alarm has a class ID of 24 and an event ID of 24003.

Separate the values with a comma.
takes effect
After you edit your onconfig file and restart the database server.


Set the SHMVIRT_ALLOGSEG configuration parameter to proactively add shared memory segments instead of waiting until the database server automatically adds shared memory segments.

The event alarm repeats every thirty minutes if a new memory segment cannot be allocated.

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