Caché Installation Guide - InterSystems Documentation

Calculating System Parameters for UNIX and Linux
Kernel
Parameter
SEMMSL
SHMALL
SHMMNI
SHMSEG
SHMMAX
Minimum Recommended Value
See SEMMNI
60 KB or ...
1000 + total global buffer space+
total routine buffer space *
3
3
60 KB or ...
1000 + total global buffer space+
total routine buffer space
Definition
Maximum number of semaphores
per identifier list.
Maximum total shared memory
system-wide. Units should be in
KB. 1000 represents the
MCOMMON shared region.
Maximum number of shared
memory identifiers system-wide.
Number of attached shared
memory segments per process.
Maximum shared memory segment
size in KB.
* This is the minimum value for SHMALL required for Caché UNIX. You must also take into
account any other applications that use shared memory. If you are unsure of other shared
memory use, calculate SHMALL as SHMSEG multiplied by SHMMAX, in pages; this larger
value will suffice in all cases.
Important:
Enough swap space must be created to support the memory allocated, unless
the operating system documentation explicitly state otherwise. On certain
operating systems (Solaris, for example) Caché creates “locked shared
memory segments” , which are not pageable. However these memory segments
still need swap space unless the operating system documentation states otherwise.
B.2.2 Platform Configuration Issues
The following sections contain configuration issues for some individual platforms. For more
information, consult the system documentation for your platform.
• Tru64 UNIX Platform Notes
• HP-UX Platform Notes
• AIX Platform Notes
• Red Hat Linux Platform Notes
76 Caché Installation Guide