IBM 000-8697 Manuel D’Utilisation

IBM Informix OnLine Database Server Administrator’s Guide

After the checkpoint completes, the tbinit daemon takes OnLine to quiescent
mode. All configuration information in the tbinit private data space is
written to the second reserved page in the initial chunk of the root dbspace,

PAGE_CONFIG

. If tbinit was executed with the -s option, OnLine remains in

quiescent mode. Otherwise, tbinit takes OnLine to online mode.

Once OnLine reaches its destination mode, either quiescent or online, the
tbinit

daemon reads the value of

RESIDENT

, the configuration parameter that

describes shared-memory residency. If

RESIDENT

 is set to 1, tbinit calls the

utility process, which tries to enforce residency of shared memory. If

the host

UNIX

 system does not support forced residency, the initialization

procedure continues and residency is not enforced. An error is returned.

Setting residency is the last initialization task that the daemon performs.
After the

RESIDENT

 parameter is processed, the tbinit daemon remains

running indefinitely. From this point forward, tbinit serves as the OnLine
master daemon.

Nine

UNIX

configuration parameters can affect the use of shared memory by

OnLine. (Parameter names are not provided because they vary among
platforms. Not all parameters exist on all platforms.)

For specific information about your

UNIX

environment, refer to the machine-

specific file, $

, that arrived with the

OnLine product.

Six of the nine parameters are kernel parameters:

■

T

he maximum shared-memory segment size, expressed in kilobytes

or bytes

■

T

he minimum shared-memory segment size, expressed in bytes

■

T

he maximum number of shared-memory identifiers