Superior Performance And Scalability; Economy And Performance - Red Hat ENTERPRISE LINUX 5 - GLOBAL FILE SYSTEM Manual

Note
The deployment examples in this chapter reflect basic configurations; your needs might
require a combination of configurations shown in the examples.

1.2.1. Superior Performance and Scalability

You can obtain the highest shared-file performance when applications access storage directly. The
GFS SAN configuration in
files and file systems. Linux applications run directly on GFS nodes. Without file protocols or storage
servers to slow data access, performance is similar to individual Linux servers with directly connected
storage; yet, each GFS application node has equal access to all data files. GFS supports up to 125
GFS nodes.
Figure 1.1. GFS with a SAN

1.2.2. Economy and Performance

Multiple Linux client applications on a LAN can share the same SAN-based data as shown in
Figure 1.2, "GFS and GNBD with a
storage devices by GNBD servers. From the perspective of a client application, storage is accessed as
if it were directly attached to the server in which the application is running. Stored data is actually on
the SAN. Storage devices and data can be equally shared by network client applications. File locking
and sharing functions are handled by GFS for each network client.
Note
Clients implementing ext2 and ext3 file systems can be configured to access their own
dedicated slice of SAN storage.
Figure 1.1, "GFS with a SAN"
SAN". SAN block storage is presented to network clients as block
Superior Performance and Scalability
provides superior file performance for shared
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