Print servers and printers are the key components needed for printing. You can size and optimize both print servers and printers in many ways.
Tip
Optimize and monitor after installation as well
After sizing and optimization, you should consider optimizing the way printing is handled using print queues. To better support deployed print services, you can periodically monitor performance, check for and install print driver upgrades, and prepare for print server failure.
The maximum load and performance level of a print server depends on its configuration. Print servers can be configured in many ways, and as a print server's workload changes over time, so should its configuration. As the workload of the print server scales, so does the amount of processing and memory required to handle print services. Any computer, including a desktop-class system, can act as a print server. The print server's central processing unit (CPU) speed, total random access memory (RAM), and network card speed should be considered.
When PCL printers and EMF print drivers are used, most of the document processing is performed on the server and the server will need a fairly fast processor and sufficient RAM to process documents. When PostScript printers and RAW print drivers are used, most of the document processing is performed on clients before documents are transferred to the server and the server's processor speed and memory are less important. In many cases, a printer server will provide services for multiple printers so there's a good chance that some of the printers will be PCL and some of the printers will be PostScript. In this case, the processing power and total RAM of the print server are again important.
Complex print jobs, such as those containing graphics, can use additional resources on the print server. They require more memory to process and more processing power. The number of clients connecting to a print server can also affect resource requirements:
Most print clients running Windows 2000 or later establish RPC connections to print servers. With RPC, a connection between a client and server remains open as long as there is one or more open handles. Typically, applications open handles to a print server when a user prints but don't close those open handles until the user shuts down or exits the application. If a user accesses the printer folder or views the printer queue on the print server, this opens handles to the print server because the folders or queues are open as well. As a result, there can be many open handles to a print server using resources even when a printer server isn't busy.
Most non-Windows clients establish Server Message Block (SMB) connections to print servers. If Print Services for Unix are configured, SMB clients running UNIX, Mac OS X, or other operating systems can use the LPR service to communicate with the LDP service on the print server. Because these clients maintain their own printer spools, the print server acts as the gateway between the client and the printer. These clients use very little resources on the server, but have very few options.
Note
Microsoft Windows 95, Windows 98, and Windows Millennium Edition (Windows Me) clients use SMB connections as well. These clients do not, however, use LPR or the LPD service. They render files using the GDI and spool RAW-formatted files to the print server. This means they perform their own processing of printed documents.
Print servers must have sufficient disk space to handle print jobs. The amount of disk space required depends on the size of print jobs and the number of print jobs that are queued for printing at any one time. It also depends on the print server configuration because in some cases a print server can be configured to save documents after they have been spooled for faster reprinting. By default, print jobs are spooled to files on the print server's system drive (%SystemRoot%System32SpoolPRINTERS), but this is completely configurable, as discussed in the section entitled "Configuring Print Spool, Logging, and Notification Settings" later in this chapter.
Print servers perform a substantial amount of disk input/output (I/O) operations. To ensure optimal performance, you should consider moving the spool folder to a separate drive or array of drives that isn't used for other purposes. A separate drive should help to ensure disk space isn't a constraint on the number of jobs the print server can handle and that the disk I/O operations related to the spooler are separate from that of other disk I/O operations.
Tip
Paging and spooling are both disk I/O-intensive operations. If possible, use a separate disk that uses a separate Small Computer System Interface (SCSI) controller rather than the disk and controller used for the server's paging file.
The network interfaces on a print server are also important, but often overlooked. The print server needs sufficient connectivity to communicate with both clients and printers. You should use 100-megabits-per-second (Mbps) network cards when possible.
Finally, when working with a dedicated print server, you should configure the Server service to Maximize Performance For File Sharing, as discussed in the section entitled "Tuning Data Throughput". This setting optimizes Windows for file and printer sharing by increasing the amount of memory reserved for the system cache and maximizing data throughput for file sharing.
Many types of printers are available including ink-jet and laser. Both types have advantages and disadvantages.
Ink-jet printers typically have lower upfront costs but higher costs later because they often require more maintenance and use consumables (ink cartridges) quicker. A typical ink-jet printer will print several hundred pages before you have to replace its ink cartridges. Highercapacity cartridges are available for some business-class models. As part of periodic maintenance, you must perform nozzle checks to check for clogged nozzles and then clean the print heads if they are clogged. You might also need to align the print heads periodically.
Laser printers typically have higher upfront costs and moderate incremental costs because these printers typically require less maintenance and use consumables (ink cartridges and OPC kits) less frequently. A typical laser printer will print several thousand pages before you have to replace ink cartridges and about 10,000 pages before you have to replace the OPC kit. Higher-capacity ink cartridges are also available for most business-class models. Replacing the ink cartridges and the OPC kit are the key maintenance tasks.
Tip
Use laser printers for high-volume printing
In most cases, laser printers have a lower per-sheet print cost than ink-jet printers. This is true for black-and-white as well as color printing. Because of the lower cost, longer life cycle of consumables, and less frequent preventative maintenance schedule, laser printers are better suited to high-volume printing.
For either printer type, you should look at the included features and the expansion options available (if any). Most business-class printers can be expanded. The options available depend on the printer model and can include the following:
RAM expansion modules The amount of RAM on a printer determines how much information it can buffer. At a minimum, a printer should be sized so that the average document being printed can be buffered in RAM in its entirety. As the workload of the printer increases, the RAM should allow for buffering of multiple documents simultaneously, which allows for faster and more efficient printing.
Tip
Consider the type of document being printed
Most word-processing documents are relatively small—several hundred pages of text use only a few hundred kilobytes. When you add in graphics, such as with presentations or Portable Document Format (PDF) files, even files with few pages can use several megabytes of disk space. Digital art, computer-aided design (CAD), and other types of files with highresolution graphics can use hundreds of megabytes.
Paper or envelope trays Add-on paper or envelope trays can improve performance substantially—more than you'd think. If a group within the organization routinely prints with different paper sizes or prints transparencies or envelopes, you should consider getting an add-on tray to accommodate the additional paper size or type. Otherwise, every time someone prints to the alternate paper size or type, the printer can stop and wait for the user to insert the appropriate type of paper. On a busy printer, this can lead to big delays in printing, frustrated users, and major problems.
Duplexers Duplexers allow for printing on both sides of a sheet of paper. If a printer has a duplexer, Windows Server 2003 will use that feature automatically to reduce the amount of paper used by the printer. This doesn't necessarily save time, but it does mean the printer's tray will have to be refilled less frequently. Users can of course change the default settings and elect not to duplex.
Internal hard disks An internal hard disk shifts much of the printing burden from the print server to the printer itself. A printer with an internal hard disk is able to store many documents internally and queue them for printing directly. Because the documents are stored on the server, printing is more efficient and can be quicker than if the printer had to wait for documents to be transferred over the network.
Many groups of users have specific needs, so if you are purchasing a printer for a particular group be sure to ask their needs, which might include the need for the following:
Photo printing Usually an option for ink-jet printers rather than laser jet printers
Large-format printing The capability to print documents larger than 11 by 17 inches
Both ink-jet and laser jet printers are available in direct-attached and network-attached models. Direct-attached printers (more commonly known as local printers) connect directly to a print server by a parallel, universal serial bus (USB) or FireWire (IEEE 1394) interface. For faster transmission speeds and easier configuration, consider printers with USB 2 or FireWire interfaces and stay away from those with slower parallel interfaces. USB and FireWire interfaces are also fully Plug and Play–compliant.
Network-attached printers have a network card and connect to the network like other devices with network cards. A printer with a built-in network interface gives you flexibility in where you place the printer relative to the print server. Unlike a local printer, which must be placed in close proximity to the print server, a network-attached printer can be placed just anywhere with a network connection. If you have a choice, choose a network-attached printer over a local printer.
Inside Out: The ins and outs of color printing
The price of color printers and the per-sheet cost of printing in color have both dropped substantially over the years. This makes color printing more affordable than ever and that has led many organizations to increase their use of color printers. If your organization is considering the use of color printers, you should look closely at the type of ink or toner cartridges used by the printer.
Most business-class color printers have separate cartridges for each basic color—cyan, magenta, and yellow—and black. Some high-end printers have additional cartridges for producing true-to-life colors, and these printers are often referred to be the number of ink/ toner cartridges, such as a six-color printer. Look closely at the capacity options for cartridges. Some printers can use both standard-capacity and high-capacity cartridges, but not always for both color and black ink.
If a group or individual needs a printer for photo printing, it is important to consider whether special photo ink/toner cartridges are available. For example, some Hewlett-Packard (HP) DeskJet models have the option to use a photo ink cartridge. This special cartridge prints digital photos with richer colors that are more true to life. Also, don't assume a color laser printer will be able to print on specialty photo paper because this might or might not be the case. See the section entitled "Configuring Color Profiles" later in this chapter for details on how Integrated Color Management (ICM) is used in Windows Server 2003.