UNIX for Advanced & Expert Users

Anybody knows how to setup Maximum number of threads per user or some other value on Sun Solaris 8.

File: /etc/system

parameter: segkpsize

Description:

Specify the amount of kernel pageable memory
available. This memory is used primarily for
kernel thread stacks. Increasing this number
allows either larger stacks for the same number
of threads or more threads. This parameter can
only be set on systems running 64-bit kernels
Systems running 64-bit kernels use a default
stack size of 24 Kbytes.

Data Type: Unsigned long

Default: 64-bit kernels, 2 Gbytes
32-bit kernels, 512 Mbytes

Range: 64-bit kernels, 512 Mbytes - 24 Gbytes
32-bit kernels, 512 Mbytes

Units: Mbytes

Dynamic? No

Validation:
Value is compared to minimum and maximum
sizes (512 Mbytes and 24 Gbytes for 64-bit
systems) and if smaller than the minimum or
larger than the maximum, it is reset to 2 Gbytes
and a message to that effect is displayed.
The actual size used in creation of the cache is
the lesser of the value specified in segkpsize
after the constraints checking and 50% of
physical memory.

When to Change: This is one of the steps necessary to support largenumbers of processes on a system. The default
size of 2 Gbytes, assuming at least 1 Gbyte of
physical memory is present, allows creation of
24-Kbyte stacks for more than 87,000 kernel
threads. The size of a stack in a 64-bit kernel is
the same whether the process is a 32-bit process
or a 64-bit process. If more than this number is
needed, segkpsize can be increased assuming
sufficient physical memory exists.

See also nfs:nfs_max_threads if you use NFS.

Regards. Hugo.