<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE chapter SYSTEM "chapter.dtd"> <chapter> <header> <copyright> <year>1997</year> <year>2016</year> <holder>Ericsson AB, All Rights Reserved</holder> </copyright> <legalnotice> Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. The Initial Developer of the Original Code is Ericsson AB. </legalnotice> <title>Erlang on embedded systems</title> <prepared>Fredrik Tillman</prepared> <responsible></responsible> <docno>ETX/B/SFP/TILLMAN:96-001</docno> <approved></approved> <checked></checked> <date>1997-11-12</date> <rev>PA1</rev> <file>intro.sgml</file> </header> <p>This manual is a complement to the other manuals and describes how to install, run and maintain Erlang on an embedded system. </p> <p>For more informaton about how to install and start Erlang read XXXXXXXX. </p> <section> <title>Memory Usage</title> <p>Solaris takes about 17 Mbyte of RAM on a system with 64 Mbyte of total RAM. This leaves about 47 Mbyte for the applications. If the system utilizes swapping, these figures cannot be improved because unnecessary daemon processes are swapped out. However, if swapping is disabled, or if the swap space is a precious resource in the system, it becomes necessary to kill off unnecessary daemon processes. </p> <p>The following start-scripts can be deleted to prevent unnecessary daemons from starting: </p> <list type="bulleted"> <item><c>/etc/rc2.d/S72autoinstall</c></item> <item><c>/etc/rc2.d/S74autofs</c></item> <item><c>/etc/rc2.d/S76nscd</c></item> <item><c>/etc/rc2.d/S80PRESERVE</c></item> <item><c>/etc/rc2.d/S80lp</c></item> <item><c>/etc/rc2.d/S88sendmail</c></item> <item><c>/etc/rc2.d/S92volmgt</c></item> <item><c>/etc/rc2.d/S93cacheos.finish</c></item> <item><c>/etc/rc3.d/S15nfs.server</c></item> </list> <p>More information is expected from Sun on how to modify the kernel in order to reduce the memory consumption. This will be performed by modifying the <c>/etc/system</c> file.</p> </section> <section> <title>Disk Space Usage</title> <p>The disk space required by Solaris can be minimized by using the Core User support installation. It requires about 80 Mbyte of disk space. This installs only the minimum software required to boot and run Solaris. The disk space can be further reduced by deleting unnecessary individual files. However, unless disk space is a critical resource the effort required and the risks involved may not be justified.</p> </section> <section> <title>Other Issues</title> <p>Future releases of OTP will include more information on how Solaris can be configured for use with embedded systems to get maximum performance. Issues which will be investigated include: </p> <list type="bulleted"> <item>how disabling swapping affects the system</item> <item>how locking processes in memory may yield performance benefits.</item> </list> </section> </chapter>