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 <H1>CUPS Software Performance Specification</H1></A><BR>
 CUPS-SPS-1.2<BR>
 Easy Software Products<BR>
 Copyright 1997-2003, All Rights Reserved<BR>
 </CENTER>
 <HR>
 <H1 ALIGN="CENTER"><A NAME="CONTENTS">Table of Contents</A></H1>
 <BR>
 <BR><B><A HREF="#1">1 Scope</A></B>
 <UL>
 <LI><A HREF="#1_1">1.1 Identification</A></LI>
 <LI><A HREF="#1_2">1.2 System Overview</A></LI>
 <LI><A HREF="#1_3">1.3 Document Overview</A></LI>
 </UL>
 <B><A HREF="#2">2 References</A></B>
 <UL>
 <LI><A HREF="#2_1">2.1 CUPS Documentation</A></LI>
 <LI><A HREF="#2_2">2.2 Other Documents</A></LI>
 </UL>
 <B><A HREF="#3">3 Programs</A></B>
 <BR>
 <BR><B><A HREF="#4">4 Scheduler Objects</A></B>
 <BR>
 <BR><B><A HREF="#5">A Glossary</A></B>
 <UL>
 <LI><A HREF="#5_1">A.1 Terms</A></LI>
 <LI><A HREF="#5_2">A.2 Acronyms</A></LI>
 </UL>
 <HR>
 <H1><A NAME="1">1 Scope</A></H1>
 <H2><A NAME="1_1">1.1 Identification</A></H2>
 <P>This software performance specification provides an analysis of the
  memory, disk, and processor utilitization of each program in the Common
  UNIX Printing System (&quot;CUPS&quot;) Version 1.2.</P>
 <P>For the purposes of comparison, all figures are for the Linux Intel
  platform. Memory utilization on other platforms should be similar.</P>
 <H2><A NAME="1_2">1.2 System Overview</A></H2>
 <P>CUPS provides a portable printing layer for UNIX&reg;-based operating
  systems. It has been developed by<A HREF="http://www.easysw.com"> Easy
  Software Products</A> to promote a standard printing solution for all
  UNIX vendors and users. CUPS provides the System V and Berkeley
  command-line interfaces.</P>
 <P>CUPS uses the Internet Printing Protocol (&quot;IPP&quot;) as the basis for
  managing print jobs and queues. The Line Printer Daemon (&quot;LPD&quot;) Server
  Message Block (&quot;SMB&quot;), and AppSocket (a.k.a. JetDirect) protocols are
  also supported with reduced functionality. CUPS adds network printer
  browsing and PostScript Printer Description (&quot;PPD&quot;) based printing
  options to support real-world printing under UNIX.</P>
 <P>CUPS also includes a customized version of GNU Ghostscript (currently
  based off GNU Ghostscript 5.50) and an image file RIP that are used to
  support non-PostScript printers. Sample drivers for HP and EPSON
  printers are included that use these filters.</P>
 <H2><A NAME="1_3">1.3 Document Overview</A></H2>
 <P>This software performance specification is organized into the
  following sections:</P>
 <UL>
 <LI>1 - Scope</LI>
 <LI>2 - References</LI>
 <LI>3 - Programs</LI>
 <LI>4 - Scheduler Objects</LI>
 <LI>A - Glossary</LI>
 </UL>
 <H1><A NAME="2">2 References</A></H1>
 <H2><A NAME="2_1">2.1 CUPS Documentation</A></H2>
 <P>The following CUPS documentation is referenced by this document:</P>
 <UL>
 <LI>CUPS-CMP-1.2: CUPS Configuration Management Plan</LI>
 <LI>CUPS-IDD-1.2: CUPS System Interface Design Description</LI>
 <LI>CUPS-IPP-1.2: CUPS Implementation of IPP</LI>
 <LI>CUPS-SAM-1.2.x: CUPS Software Administrators Manual</LI>
 <LI>CUPS-SDD-1.2: CUPS Software Design Description</LI>
 <LI>CUPS-SPM-1.2.x: CUPS Software Programming Manual</LI>
 <LI>CUPS-SSR-1.2: CUPS Software Security Report</LI>
 <LI>CUPS-STP-1.2: CUPS Software Test Plan</LI>
 <LI>CUPS-SUM-1.2.x: CUPS Software Users Manual</LI>
 <LI>CUPS-SVD-1.2: CUPS Software Version Description</LI>
 </UL>
 <H2><A NAME="2_2">2.2 Other Documents</A></H2>
 <P>The following non-CUPS documents are referenced by this document:</P>
 <UL>
 <LI><A HREF="http://partners.adobe.com/asn/developer/PDFS/TN/5003.PPD_Spec_v4.3.pdf">
 Adobe PostScript Printer Description File Format Specification, Version
  4.3.</A></LI>
 <LI><A HREF="http://partners.adobe.com/asn/developer/PDFS/TN/PLRM.pdf">
 Adobe PostScript Language Reference, Third Edition.</A></LI>
 <LI>IPP: Job and Printer Set Operations</LI>
 <LI>IPP/1.1: Encoding and Transport</LI>
 <LI>IPP/1.1: Implementers Guide</LI>
 <LI>IPP/1.1: Model and Semantics</LI>
 <LI><A HREF="http://www.ietf.org/rfc/rfc1179.txt">RFC 1179, Line Printer
  Daemon Protocol</A></LI>
 <LI><A HREF="http://www.ietf.org/rfc/rfc2567.txt">RFC 2567, Design Goals
  for an Internet Printing Protocol</A></LI>
 <LI><A HREF="http://www.ietf.org/rfc/rfc2568.txt">RFC 2568, Rationale
  for the Structure of the Model and Protocol for the Internet Printing
  Protocol</A></LI>
 <LI><A HREF="http://www.ietf.org/rfc/rfc2569.txt">RFC 2569, Mapping
  between LPD and IPP Protocols</A></LI>
 <LI><A HREF="http://www.ietf.org/rfc/rfc2616.txt">RFC 2616, Hypertext
  Transfer Protocol -- HTTP/1.1</A></LI>
 <LI><A HREF="http://www.ietf.org/rfc/rfc2617.txt">RFC 2617, HTTP
  Authentication: Basic and Digest Access</A> Authentication</LI>
 </UL>
 <H1><A NAME="3">3 Programs</A></H1>
 <P>The following table describes the average memory, disk, and CPU usage
  of each program in CUPS.</P>
 <P>The base memory column shows the initial memory requirements for each
  program, including any shared libraries that are provided by CUPS.</P>
 <P>The max memory column shows the maximum amount of memory that will be
  used by the program based upon the default configuration settings
  supplied with CUPS.</P>
 <P>The temp files column indicates whether any temporary files are
  created.</P>
 <P>The CPU usage column specifies a relative CPU usage by the program
  under normal conditions, either low, medium, or high. Low usage
  indicates that the program will never use more than 33% of the
  available CPU time. Medium usage indicates the program will use as much
  as 66% of the available CPU time. High usage indicates the program uses
  66% or more of the available CPU time.
 <CENTER>
 <TABLE BORDER="1" WIDTH="80%">
 <TR><TH COLSPAN="3">Backends</TH></TR>
 <TR><TH>Program</TH><TH>Base Memory</TH><TH>Max Memory</TH><TH>Temp
  Files</TH><TH>CPU Usage</TH></TR>
 <TR><TD>ipp</TD><TD>91k</TD><TD>256k</TD><TD>Up to size of print file</TD><TD>
 Low</TD></TR>
 <TR><TD>lpd</TD><TD>89k</TD><TD>89k</TD><TD>Up to size of print file</TD><TD>
 Low</TD></TR>
 <TR><TD>parallel</TD><TD>85k</TD><TD>85k</TD><TD>Up to size of print
  file</TD><TD>Low</TD></TR>
 <TR><TD>serial</TD><TD>85k</TD><TD>85k</TD><TD>Up to size of print file</TD><TD>
 Low</TD></TR>
 <TR><TD>socket</TD><TD>85k</TD><TD>85k</TD><TD>Up to size of print file</TD><TD>
 Low</TD></TR>
 <TR><TD>usb</TD><TD>85k</TD><TD>85k</TD><TD>Up to size of print file</TD><TD>
 Low</TD></TR>
 <TR><TH COLSPAN="3">CGIs</TH></TR>
 <TR><TH>Program</TH><TH>Base Memory</TH><TH>Max Memory</TH><TH>Temp
  Files</TH><TH>CPU Usage</TH></TR>
 <TR><TD>admin.cgi</TD><TD>107k</TD><TD>256k</TD><TD>Up to size of PPD
  file</TD><TD>Medium</TD></TR>
 <TR><TD>classes.cgi</TD><TD>95k</TD><TD>Size of class objects</TD><TD>
 None</TD><TD>Medium</TD></TR>
 <TR><TD>jobs.cgi</TD><TD>93k</TD><TD>Size of job objects</TD><TD>None</TD><TD>
 Medium</TD></TR>
 <TR><TD>printers.cgi</TD><TD>95k</TD><TD>Size of printer objects</TD><TD>
 None</TD><TD>Medium</TD></TR>
 <TR><TH COLSPAN="3">Command-Line Programs</TH></TR>
 <TR><TH>Program</TH><TH>Base Memory</TH><TH>Max Memory</TH><TH>Temp
  Files</TH><TH>CPU Usage</TH></TR>
 <TR><TD>accept</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>cancel</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>disable</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>enable</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>lp</TD><TD>90k</TD><TD>256k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>lpadmin</TD><TD>148k</TD><TD>256k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>lpc</TD><TD>86k</TD><TD>Size of job and printer objects</TD><TD>
 None</TD><TD>Medium</TD></TR>
 <TR><TD>lpinfo</TD><TD>89k</TD><TD>Size of device and PPD objects</TD><TD>
 None</TD><TD>Medium</TD></TR>
 <TR><TD>lpmove</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>lpoptions</TD><TD>89k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>lppasswd</TD><TD>90k</TD><TD>90k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>lpq</TD><TD>87k</TD><TD>Size of job objects</TD><TD>None</TD><TD>
 Medium</TD></TR>
 <TR><TD>lpr</TD><TD>87k</TD><TD>256k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>lprm</TD><TD>84k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>lpstat</TD><TD>119k</TD><TD>Size of job, printer, and class
  objects</TD><TD>None</TD><TD>Medium</TD></TR>
 <TR><TD>reject</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TH COLSPAN="3">Daemons</TH></TR>
 <TR><TH>Program</TH><TH>Base Memory</TH><TH>Max Memory</TH><TH>Temp
  Files</TH><TH>CPU Usage</TH></TR>
 <TR><TD>cups-lpd</TD><TD>92k</TD><TD>256k</TD><TD>One file per control
  or data file from client</TD><TD>Low</TD></TR>
 <TR><TD>cupsd</TD><TD>308k</TD><TD>See Scheduler Requirements</TD><TD>
 See Scheduler Requirements</TD><TD>Medium</TD></TR>
 <TR><TD>cups-polld</TD><TD>84k</TD><TD>Size of printer and class objects</TD><TD>
 None</TD><TD>Low</TD></TR>
 <TR><TH COLSPAN="3">Filters</TH></TR>
 <TR><TH>Program</TH><TH>Base Memory</TH><TH>Max Memory</TH><TH>Temp
  Files</TH><TH>CPU Usage</TH></TR>
 <TR><TD>hpgltops</TD><TD>263k</TD><TD>320k</TD><TD>None</TD><TD>Medium</TD>
 </TR>
 <TR><TD>imagetops</TD><TD>628k</TD><TD>10M</TD><TD>Swap file for
  uncompressed image data</TD><TD>Medium</TD></TR>
 <TR><TD>imagetoraster</TD><TD>652k</TD><TD>10M</TD><TD>Swap file for
  uncompressed image data</TD><TD>High</TD></TR>
 <TR><TD>pstops</TD><TD>775k</TD><TD>840k</TD><TD>Up to size of print
  file</TD><TD>Medium</TD></TR>
 <TR><TD>pstoraster</TD><TD>4M</TD><TD>14M</TD><TD>Swap file for command
  lists</TD><TD>High</TD></TR>
 <TR><TD>rastertoepson</TD><TD>693k</TD><TD>1M</TD><TD>None</TD><TD>Low</TD>
 </TR>
 <TR><TD>rastertohp</TD><TD>690k</TD><TD>1M</TD><TD>None</TD><TD>Low</TD></TR>
 <TR><TD>texttops</TD><TD>638k</TD><TD>4*cols*rows</TD><TD>None</TD><TD>
 Low</TD></TR>
 </TABLE>
 </CENTER>
 </P>
 <H1><A NAME="4">4 Scheduler Objects</A></H1>
 <P>The <CODE>cupsd</CODE> program is the CUPS scheduler process. It
  manages many interdependent server objects that are used to manage and
  print files to printers.</P>
 <P>The following table provides the memory and disk cost associated with
  each server object.
 <CENTER>
 <TABLE BORDER="1" WIDTH="80%">
 <TR><TH>Object</TH><TH>Memory Per</TH><TH>Disk Per</TH></TR>
 <TR><TD>Browse ACL</TD><TD>1k</TD><TD>120</TD></TR>
 <TR><TD>Browse Poll</TD><TD>24</TD><TD>80</TD></TR>
 <TR><TD>Browse Relay</TD><TD>28</TD><TD>80</TD></TR>
 <TR><TD>Certificate</TD><TD>76</TD><TD>32</TD></TR>
 <TR><TD>Class</TD><TD>9k</TD><TD>200</TD></TR>
 <TR><TD>Client</TD><TD>13k</TD><TD>-</TD></TR>
 <TR><TD>Device</TD><TD>256</TD><TD>-</TD></TR>
 <TR><TD>Job</TD><TD>2k</TD><TD>1k + size of document files</TD></TR>
 <TR><TD>Location ACL</TD><TD>1k</TD><TD>120</TD></TR>
 <TR><TD>MIME Filter</TD><TD>268</TD><TD>80</TD></TR>
 <TR><TD>MIME Type</TD><TD>340</TD><TD>80</TD></TR>
 <TR><TD>PPD</TD><TD>200</TD><TD>656</TD></TR>
 <TR><TD>Printer</TD><TD>11k</TD><TD>32k</TD></TR>
 </TABLE>
 </CENTER>
 </P>
 <H1 TYPE="A" VALUE="1"><A NAME="5">A Glossary</A></H1>
 <H2><A NAME="5_1">A.1 Terms</A></H2>
 <DL>
 <DT>C</DT>
 <DD>A computer language.</DD>
 <DT>parallel</DT>
 <DD>Sending or receiving data more than 1 bit at a time.</DD>
 <DT>pipe</DT>
 <DD>A one-way communications channel between two programs.</DD>
 <DT>serial</DT>
 <DD>Sending or receiving data 1 bit at a time.</DD>
 <DT>socket</DT>
 <DD>A two-way network communications channel.</DD>
 </DL>
 <H2><A NAME="5_2">A.2 Acronyms</A></H2>
 <DL>
 <DT>ASCII</DT>
 <DD>American Standard Code for Information Interchange</DD>
 <DT>CUPS</DT>
 <DD>Common UNIX Printing System</DD>
 <DT>ESC/P</DT>
 <DD>EPSON Standard Code for Printers</DD>
 <DT>FTP</DT>
 <DD>File Transfer Protocol</DD>
 <DT>HP-GL</DT>
 <DD>Hewlett-Packard Graphics Language</DD>
 <DT>HP-PCL</DT>
 <DD>Hewlett-Packard Page Control Language</DD>
 <DT>HP-PJL</DT>
 <DD>Hewlett-Packard Printer Job Language</DD>
 <DT>IETF</DT>
 <DD>Internet Engineering Task Force</DD>
 <DT>IPP</DT>
 <DD>Internet Printing Protocol</DD>
 <DT>ISO</DT>
 <DD>International Standards Organization</DD>
 <DT>LPD</DT>
 <DD>Line Printer Daemon</DD>
 <DT>MIME</DT>
 <DD>Multimedia Internet Mail Exchange</DD>
 <DT>PPD</DT>
 <DD>PostScript Printer Description</DD>
 <DT>SMB</DT>
 <DD>Server Message Block</DD>
 <DT>TFTP</DT>
 <DD>Trivial File Transfer Protocol</DD>
 </DL>
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	<CENTER><A HREF="#CONTENTS"><IMG SRC="images/cups-large.gif" BORDER="0" WIDTH="431" HEIGHT="511"><BR>
	<H1>CUPS Software Performance Specification</H1></A><BR>
	CUPS-SPS-1.2<BR>
	Easy Software Products<BR>
	Copyright 1997-2003, All Rights Reserved<BR>
	</CENTER>
	<HR>
	<H1 ALIGN="CENTER"><A NAME="CONTENTS">Table of Contents</A></H1>
	<BR>
	<BR><B><A HREF="#1">1 Scope</A></B>
	<UL>
	<LI><A HREF="#1_1">1.1 Identification</A></LI>
	<LI><A HREF="#1_2">1.2 System Overview</A></LI>
	<LI><A HREF="#1_3">1.3 Document Overview</A></LI>
	</UL>
	<B><A HREF="#2">2 References</A></B>
	<UL>
	<LI><A HREF="#2_1">2.1 CUPS Documentation</A></LI>
	<LI><A HREF="#2_2">2.2 Other Documents</A></LI>
	</UL>
	<B><A HREF="#3">3 Programs</A></B>
	<BR>
	<BR><B><A HREF="#4">4 Scheduler Objects</A></B>
	<BR>
	<BR><B><A HREF="#5">A Glossary</A></B>
	<UL>
	<LI><A HREF="#5_1">A.1 Terms</A></LI>
	<LI><A HREF="#5_2">A.2 Acronyms</A></LI>
	</UL>
	<HR>
	<H1><A NAME="1">1 Scope</A></H1>
	<H2><A NAME="1_1">1.1 Identification</A></H2>
	<P>This software performance specification provides an analysis of the
	memory, disk, and processor utilitization of each program in the Common
	UNIX Printing System ("CUPS") Version 1.2.</P>
	<P>For the purposes of comparison, all figures are for the Linux Intel
	platform. Memory utilization on other platforms should be similar.</P>
	<H2><A NAME="1_2">1.2 System Overview</A></H2>
	<P>CUPS provides a portable printing layer for UNIX®-based operating
	systems. It has been developed by<A HREF="http://www.easysw.com"> Easy
	Software Products</A> to promote a standard printing solution for all
	UNIX vendors and users. CUPS provides the System V and Berkeley
	command-line interfaces.</P>
	<P>CUPS uses the Internet Printing Protocol ("IPP") as the basis for
	managing print jobs and queues. The Line Printer Daemon ("LPD") Server
	Message Block ("SMB"), and AppSocket (a.k.a. JetDirect) protocols are
	also supported with reduced functionality. CUPS adds network printer
	browsing and PostScript Printer Description ("PPD") based printing
	options to support real-world printing under UNIX.</P>
	<P>CUPS also includes a customized version of GNU Ghostscript (currently
	based off GNU Ghostscript 5.50) and an image file RIP that are used to
	support non-PostScript printers. Sample drivers for HP and EPSON
	printers are included that use these filters.</P>
	<H2><A NAME="1_3">1.3 Document Overview</A></H2>
	<P>This software performance specification is organized into the
	following sections:</P>
	<UL>
	<LI>1 - Scope</LI>
	<LI>2 - References</LI>
	<LI>3 - Programs</LI>
	<LI>4 - Scheduler Objects</LI>
	<LI>A - Glossary</LI>
	</UL>
	<H1><A NAME="2">2 References</A></H1>
	<H2><A NAME="2_1">2.1 CUPS Documentation</A></H2>
	<P>The following CUPS documentation is referenced by this document:</P>
	<UL>
	<LI>CUPS-CMP-1.2: CUPS Configuration Management Plan</LI>
	<LI>CUPS-IDD-1.2: CUPS System Interface Design Description</LI>
	<LI>CUPS-IPP-1.2: CUPS Implementation of IPP</LI>
	<LI>CUPS-SAM-1.2.x: CUPS Software Administrators Manual</LI>
	<LI>CUPS-SDD-1.2: CUPS Software Design Description</LI>
	<LI>CUPS-SPM-1.2.x: CUPS Software Programming Manual</LI>
	<LI>CUPS-SSR-1.2: CUPS Software Security Report</LI>
	<LI>CUPS-STP-1.2: CUPS Software Test Plan</LI>
	<LI>CUPS-SUM-1.2.x: CUPS Software Users Manual</LI>
	<LI>CUPS-SVD-1.2: CUPS Software Version Description</LI>
	</UL>
	<H2><A NAME="2_2">2.2 Other Documents</A></H2>
	<P>The following non-CUPS documents are referenced by this document:</P>
	<UL>
	<LI><A HREF="http://partners.adobe.com/asn/developer/PDFS/TN/5003.PPD_Spec_v4.3.pdf">
	Adobe PostScript Printer Description File Format Specification, Version
	4.3.</A></LI>
	<LI><A HREF="http://partners.adobe.com/asn/developer/PDFS/TN/PLRM.pdf">
	Adobe PostScript Language Reference, Third Edition.</A></LI>
	<LI>IPP: Job and Printer Set Operations</LI>
	<LI>IPP/1.1: Encoding and Transport</LI>
	<LI>IPP/1.1: Implementers Guide</LI>
	<LI>IPP/1.1: Model and Semantics</LI>
	<LI><A HREF="http://www.ietf.org/rfc/rfc1179.txt">RFC 1179, Line Printer
	Daemon Protocol</A></LI>
	<LI><A HREF="http://www.ietf.org/rfc/rfc2567.txt">RFC 2567, Design Goals
	for an Internet Printing Protocol</A></LI>
	<LI><A HREF="http://www.ietf.org/rfc/rfc2568.txt">RFC 2568, Rationale
	for the Structure of the Model and Protocol for the Internet Printing
	Protocol</A></LI>
	<LI><A HREF="http://www.ietf.org/rfc/rfc2569.txt">RFC 2569, Mapping
	between LPD and IPP Protocols</A></LI>
	<LI><A HREF="http://www.ietf.org/rfc/rfc2616.txt">RFC 2616, Hypertext
	Transfer Protocol -- HTTP/1.1</A></LI>
	<LI><A HREF="http://www.ietf.org/rfc/rfc2617.txt">RFC 2617, HTTP
	Authentication: Basic and Digest Access</A> Authentication</LI>
	</UL>
	<H1><A NAME="3">3 Programs</A></H1>
	<P>The following table describes the average memory, disk, and CPU usage
	of each program in CUPS.</P>
	<P>The base memory column shows the initial memory requirements for each
	program, including any shared libraries that are provided by CUPS.</P>
	<P>The max memory column shows the maximum amount of memory that will be
	used by the program based upon the default configuration settings
	supplied with CUPS.</P>
	<P>The temp files column indicates whether any temporary files are
	created.</P>
	<P>The CPU usage column specifies a relative CPU usage by the program
	under normal conditions, either low, medium, or high. Low usage
	indicates that the program will never use more than 33% of the
	available CPU time. Medium usage indicates the program will use as much
	as 66% of the available CPU time. High usage indicates the program uses
	66% or more of the available CPU time.
	<CENTER>
	<TABLE BORDER="1" WIDTH="80%">
	<TR><TH COLSPAN="3">Backends</TH></TR>
	<TR><TH>Program</TH><TH>Base Memory</TH><TH>Max Memory</TH><TH>Temp
	Files</TH><TH>CPU Usage</TH></TR>
	<TR><TD>ipp</TD><TD>91k</TD><TD>256k</TD><TD>Up to size of print file</TD><TD>
	Low</TD></TR>
	<TR><TD>lpd</TD><TD>89k</TD><TD>89k</TD><TD>Up to size of print file</TD><TD>
	Low</TD></TR>
	<TR><TD>parallel</TD><TD>85k</TD><TD>85k</TD><TD>Up to size of print
	file</TD><TD>Low</TD></TR>
	<TR><TD>serial</TD><TD>85k</TD><TD>85k</TD><TD>Up to size of print file</TD><TD>
	Low</TD></TR>
	<TR><TD>socket</TD><TD>85k</TD><TD>85k</TD><TD>Up to size of print file</TD><TD>
	Low</TD></TR>
	<TR><TD>usb</TD><TD>85k</TD><TD>85k</TD><TD>Up to size of print file</TD><TD>
	Low</TD></TR>
	<TR><TH COLSPAN="3">CGIs</TH></TR>
	<TR><TH>Program</TH><TH>Base Memory</TH><TH>Max Memory</TH><TH>Temp
	Files</TH><TH>CPU Usage</TH></TR>
	<TR><TD>admin.cgi</TD><TD>107k</TD><TD>256k</TD><TD>Up to size of PPD
	file</TD><TD>Medium</TD></TR>
	<TR><TD>classes.cgi</TD><TD>95k</TD><TD>Size of class objects</TD><TD>
	None</TD><TD>Medium</TD></TR>
	<TR><TD>jobs.cgi</TD><TD>93k</TD><TD>Size of job objects</TD><TD>None</TD><TD>
	Medium</TD></TR>
	<TR><TD>printers.cgi</TD><TD>95k</TD><TD>Size of printer objects</TD><TD>
	None</TD><TD>Medium</TD></TR>
	<TR><TH COLSPAN="3">Command-Line Programs</TH></TR>
	<TR><TH>Program</TH><TH>Base Memory</TH><TH>Max Memory</TH><TH>Temp
	Files</TH><TH>CPU Usage</TH></TR>
	<TR><TD>accept</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>cancel</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>disable</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>enable</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>lp</TD><TD>90k</TD><TD>256k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>lpadmin</TD><TD>148k</TD><TD>256k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>lpc</TD><TD>86k</TD><TD>Size of job and printer objects</TD><TD>
	None</TD><TD>Medium</TD></TR>
	<TR><TD>lpinfo</TD><TD>89k</TD><TD>Size of device and PPD objects</TD><TD>
	None</TD><TD>Medium</TD></TR>
	<TR><TD>lpmove</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>lpoptions</TD><TD>89k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>lppasswd</TD><TD>90k</TD><TD>90k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>lpq</TD><TD>87k</TD><TD>Size of job objects</TD><TD>None</TD><TD>
	Medium</TD></TR>
	<TR><TD>lpr</TD><TD>87k</TD><TD>256k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>lprm</TD><TD>84k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>lpstat</TD><TD>119k</TD><TD>Size of job, printer, and class
	objects</TD><TD>None</TD><TD>Medium</TD></TR>
	<TR><TD>reject</TD><TD>88k</TD><TD>128k</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TH COLSPAN="3">Daemons</TH></TR>
	<TR><TH>Program</TH><TH>Base Memory</TH><TH>Max Memory</TH><TH>Temp
	Files</TH><TH>CPU Usage</TH></TR>
	<TR><TD>cups-lpd</TD><TD>92k</TD><TD>256k</TD><TD>One file per control
	or data file from client</TD><TD>Low</TD></TR>
	<TR><TD>cupsd</TD><TD>308k</TD><TD>See Scheduler Requirements</TD><TD>
	See Scheduler Requirements</TD><TD>Medium</TD></TR>
	<TR><TD>cups-polld</TD><TD>84k</TD><TD>Size of printer and class objects</TD><TD>
	None</TD><TD>Low</TD></TR>
	<TR><TH COLSPAN="3">Filters</TH></TR>
	<TR><TH>Program</TH><TH>Base Memory</TH><TH>Max Memory</TH><TH>Temp
	Files</TH><TH>CPU Usage</TH></TR>
	<TR><TD>hpgltops</TD><TD>263k</TD><TD>320k</TD><TD>None</TD><TD>Medium</TD>
	</TR>
	<TR><TD>imagetops</TD><TD>628k</TD><TD>10M</TD><TD>Swap file for
	uncompressed image data</TD><TD>Medium</TD></TR>
	<TR><TD>imagetoraster</TD><TD>652k</TD><TD>10M</TD><TD>Swap file for
	uncompressed image data</TD><TD>High</TD></TR>
	<TR><TD>pstops</TD><TD>775k</TD><TD>840k</TD><TD>Up to size of print
	file</TD><TD>Medium</TD></TR>
	<TR><TD>pstoraster</TD><TD>4M</TD><TD>14M</TD><TD>Swap file for command
	lists</TD><TD>High</TD></TR>
	<TR><TD>rastertoepson</TD><TD>693k</TD><TD>1M</TD><TD>None</TD><TD>Low</TD>
	</TR>
	<TR><TD>rastertohp</TD><TD>690k</TD><TD>1M</TD><TD>None</TD><TD>Low</TD></TR>
	<TR><TD>texttops</TD><TD>638k</TD><TD>4colsrows</TD><TD>None</TD><TD>
	Low</TD></TR>
	</TABLE>
	</CENTER>
	</P>
	<H1><A NAME="4">4 Scheduler Objects</A></H1>
	<P>The <CODE>cupsd</CODE> program is the CUPS scheduler process. It
	manages many interdependent server objects that are used to manage and
	print files to printers.</P>
	<P>The following table provides the memory and disk cost associated with
	each server object.
	<CENTER>
	<TABLE BORDER="1" WIDTH="80%">
	<TR><TH>Object</TH><TH>Memory Per</TH><TH>Disk Per</TH></TR>
	<TR><TD>Browse ACL</TD><TD>1k</TD><TD>120</TD></TR>
	<TR><TD>Browse Poll</TD><TD>24</TD><TD>80</TD></TR>
	<TR><TD>Browse Relay</TD><TD>28</TD><TD>80</TD></TR>
	<TR><TD>Certificate</TD><TD>76</TD><TD>32</TD></TR>
	<TR><TD>Class</TD><TD>9k</TD><TD>200</TD></TR>
	<TR><TD>Client</TD><TD>13k</TD><TD>-</TD></TR>
	<TR><TD>Device</TD><TD>256</TD><TD>-</TD></TR>
	<TR><TD>Job</TD><TD>2k</TD><TD>1k + size of document files</TD></TR>
	<TR><TD>Location ACL</TD><TD>1k</TD><TD>120</TD></TR>
	<TR><TD>MIME Filter</TD><TD>268</TD><TD>80</TD></TR>
	<TR><TD>MIME Type</TD><TD>340</TD><TD>80</TD></TR>
	<TR><TD>PPD</TD><TD>200</TD><TD>656</TD></TR>
	<TR><TD>Printer</TD><TD>11k</TD><TD>32k</TD></TR>
	</TABLE>
	</CENTER>
	</P>
	<H1 TYPE="A" VALUE="1"><A NAME="5">A Glossary</A></H1>
	<H2><A NAME="5_1">A.1 Terms</A></H2>
	<DL>
	<DT>C</DT>
	<DD>A computer language.</DD>
	<DT>parallel</DT>
	<DD>Sending or receiving data more than 1 bit at a time.</DD>
	<DT>pipe</DT>
	<DD>A one-way communications channel between two programs.</DD>
	<DT>serial</DT>
	<DD>Sending or receiving data 1 bit at a time.</DD>
	<DT>socket</DT>
	<DD>A two-way network communications channel.</DD>
	</DL>
	<H2><A NAME="5_2">A.2 Acronyms</A></H2>
	<DL>
	<DT>ASCII</DT>
	<DD>American Standard Code for Information Interchange</DD>
	<DT>CUPS</DT>
	<DD>Common UNIX Printing System</DD>
	<DT>ESC/P</DT>
	<DD>EPSON Standard Code for Printers</DD>
	<DT>FTP</DT>
	<DD>File Transfer Protocol</DD>
	<DT>HP-GL</DT>
	<DD>Hewlett-Packard Graphics Language</DD>
	<DT>HP-PCL</DT>
	<DD>Hewlett-Packard Page Control Language</DD>
	<DT>HP-PJL</DT>
	<DD>Hewlett-Packard Printer Job Language</DD>
	<DT>IETF</DT>
	<DD>Internet Engineering Task Force</DD>
	<DT>IPP</DT>
	<DD>Internet Printing Protocol</DD>
	<DT>ISO</DT>
	<DD>International Standards Organization</DD>
	<DT>LPD</DT>
	<DD>Line Printer Daemon</DD>
	<DT>MIME</DT>
	<DD>Multimedia Internet Mail Exchange</DD>
	<DT>PPD</DT>
	<DD>PostScript Printer Description</DD>
	<DT>SMB</DT>
	<DD>Server Message Block</DD>
	<DT>TFTP</DT>
	<DD>Trivial File Transfer Protocol</DD>
	</DL>
	</BODY>
	</HTML>