Caché Installation Guide - InterSystems Documentation

The 2-GB value is the total address space the operation system allocates for the process data,
which includes not only shared memory, but other Caché and operating system data as well.
Therefore, it represents an upper limit that is not achievable in practice.
• For 64-bit platforms:
Configure UNIX Kernel Parameters
The number of global buffers is limited only by the operating system and the available memory.
Note:
Even if your configuration is using only 2- KB databases, some of the Caché databases,
namely CACHESYS and CACHETEMP, are 8- KB. The system always sets aside a minimum
of 200 8- KB buffers for these, regardless of what you specify. In general, increase this value,
especially if you are making heavy use of Caché SQL.
Set your values to less than the maximum number of buffers.
B.1.5 Determine Number of Routine Buffers
Caché supports the following maximum value for the number of routine buffers:
65,535
Set your values to less than this maximum number of buffers.
B.1.6 Determine Maximum Number of Users
The maximum users allowed by Caché is the lowest of the following values:
• License limit
• # of semaphores - 4
B.1.7 Determine Maximum Database Size
The ulimit parameter in UNIX determines the maximum file size available to a process. For the Caché
Manager group, the value of ulimit should either be unlimited or as large as the largest database you
may have.
B.2 Configure UNIX Kernel Parameters
The following sections describe issues related to tuning and performance on various UNIX platforms:
• Set Values for Tunable UNIX Parameters
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