Kernel parameters -maximum threads per process

Question

How can we change the kernel parameters also how can we increase the maximum number of threads allowed .
How can we increase maimum perocess per used id .

Answer 1

There is no kernel parameter limiting the maximum
number of threads allowed. If you are talking about
user level threads, you will run into virtual address
space limitations at about 3000 for a process
assuming 32-bit address space and default
stack size of 1M per thread, and assuming you are
not using the alternate thread library (see threads(3thr))
or Solaris 9. If you need more than this many
threads at the same time, I suspect you are doing something
incorrectly. Otherwise, try using a smaller stack size
per thread. If you are running on Solaris 9, or using
the alternate thread library, both give you a 1x1
thread model, i.e., each user thread has a corresponding
kernel entity (lwp). In this case, you will cause
your machine to hang by eating up all available
space for lwp's. In either case, the question should be:
"how do I limit the number of threads per process?", since
there is currently no limitation other than space.
In Solaris 9, you can use resource management to
limit the number of lwp's (and therefore user threads)
per process.