09-25-2013
You can force a process to start out mostly in swap, but if the process runs at all it will wind up in RAM. Running something totally from swap is a bad idea, and if allowed, it results in a real performance drag called thrashing. The swapped process runs 100's of time slower and can seriously degrade the whole system. For every other process on the system.
If you got this idea from seeing how much memory a service is using, you may have misunderstood. A lot of the working set of a process is in shared memory. All processes use this shared memory at the same time. If each of the required system processes (services among them) had nothing but private memory, it likely would have eaten most of system memory before you even logged onto a newly booted box.
You may want to rethink this swap idea.
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LEARN ABOUT HPUX
serialize
serialize(2) System Calls Manual serialize(2)
NAME
serialize() - force target process to run serially with other processes
SYNOPSIS
DESCRIPTION
The system call is used to force the target process referenced by the pid value passed in to run serially with other processes also marked
for serialization. If the value of pid is zero, then the currently running process is marked for serialization. Once a process has been
marked by the process stays marked until process completion, unless is reissued on the serialized process with timeshare set to 1. If
timeshare is set to 1, the process specified in pid will be returned to normal timeshare scheduling algorithms.
This call is used to improve process throughput since process throughput usually increases for large processes when they are executed seri-
ally instead of allowing each program to run for only a short period of time. By running large processes one at a time, the system makes
more efficient use of the CPU as well as system memory, since each process does not end up constantly faulting in its working set, to only
have the pages stolen when another process starts running. As long as there is enough memory in the system, processes marked by behave no
differently from other processes in the system. However, once memory becomes tight, processes marked by are run one at a time with the
highest priority processes being run first. Each process runs for a finite interval of time before another serialized process is allowed
to run.
RETURN VALUE
returns zero upon successful completion, or nonzero if the system call failed.
ERRORS
If fails, it sets (see errno(2)) to the following value:
The pid passed in does not exist.
WARNINGS
The user has no way of forcing an execution order on serialized processes.
AUTHOR
was developed by HP.
SEE ALSO
serialize(1), privileges(5).
serialize(2)