VWE supports the XFS file system running on Linux platforms. XFS is a scalable, high-performance, journalling file system that SGI has contributed to the Open Source Linux community. The XFS journalling technology lets the file system restart almost immediately after an interrupt, regardless of the number of files it is managing.

XFS is a full 64-bit file system, capable of handling files as large as a million terabytes and of delivering near raw-I/O performance. For information about XFS, see the following:

http://oss.sgi.com/projects/xfs

Kernel-supported asynchronous I/O (KAIO) differs from asynchronous I/O in that it is implemented with support from kernel modifications. These kernel modifications allow KAIO to perform split-phase I/O to maximize concurrency of I/O at a device. Split-phase I/O allows the initiating request (such as an aio_read) to truly queue the I/O at the device as the first phase of the I/O request. The second phase of the I/O request, performed as part of the I/O completion, propagates results of the request. The results may include the contents of the I/O buffer on a read, the number of bytes read or written, and any error status.

For more information about KAIO, see the following URL:

http://oss.sgi.com/projects/kaio

CSA is a set of C programs and shell scripts that provide methods for collecting per-process resource usage data, monitoring disk usage, and charging fees to specific login accounts. CSA takes this per-process accounting information and combines it by job identifier (jid) within system boot uptime periods.

CSA provides the following features not available with other Linux accounting packages:

For detailed information about CSA, see the following URL:

http://oss.sgi.com/projects/csa

VWE supports the runon command, which runs a command on a particular CPU (this CPU affinity is called process pinning). The runon command can assign process pinning using fork(), or by process ID. Pinning is inherited across fork() and exec() system calls. To change the pinning, you can use the prctl(2) call. The runon(1) man page contains more information.

VWE supports the hinv command, which displays the contents of the system hardware inventory table. This table is created each time a system is booted and contains entries describing various pieces of hardware in the system. The items in the table include main memory size, cache sizes, floating point unit, and disk drives. Without arguments, the hinv command displays a one line description of each entry in the table. The hinv(1) man page contains more information.