test

SunVTS 5.0 Test Reference Manual

disktest Test Requirements

By default, disktest does not mount any partitions. To have SunVTS pre-mount all mountable partitions, set the environment variable BYPASS_FS_PROBE to 0 (zero) before starting SunVTS. Pre-mounting can be disabled by unsetting BYPASS_FS_PROBE or changing it to a value other than 0 (zero).

The mount point used by disktest is the word disktest appended by the name of the disk partition. For example, if the disk partition name is /dev/dsk/c0t3d0s0, disktest mounts it as superuser under the name /disktest_c0t3d0s0

Caution - Caution -

If a power failure occurs while the Media subtest is running in WriteRead mode, disk data may be destroyed.

Caution - Caution -

Running the Media subtest on a disk partition in the WriteRead mode may cause data corruption if the same partition is being used by other programs. Only select this mode when the system is offline (not used by any other users or programs).

disktest tests the floppy drive regardless of whether the Volume Management software is running or not. The following mount point names are used:

Loading an option file (refer to the SunVTS User's Guide for option file details) that was created when BYPASS_FS_PROBE was set to 0 (zero) might not work if the BYPASS_FS_PROBE environment variable is no longer set to 0. Testing may fail with the following error:


SUNWvts.disktest.8088 07/24/98 15:47:22 disktest c0t0d0 FATAL:

"Couldn't get file system information on /disktest_s0t0d0s0,

statvfs() system call failure error: No such file or directory.

This error is caused when SunVTS expects to use the predefined mount point names that are created when BYPASS_FS_PROBE is set to 0 (zero), but these mount points do not exist while BYPASS_FS_PROBE is not set to 0.

To use option files with disktest, create two separate option files for the two different states of the BYPASS_FS_PROBE environment variable.

Table 12-1 describes the disktest subtests.

Table 12-1 disktest Subtests

Subtest 

Description 

Media subtest 

Verifies disk media by writing data to and reading data from the disk. The Media subtest treats a disk as one large chunk of contiguous data. 

 

This is a scalable test that can run multiple copies in read/write mode on the same disk partition. To avoid data corruption, all simultaneous instances of disktest communicate through a shared memory service. This ensures that different copies of the media subtest do not overlay the same disk block at the same time.

 

The Media subtest runs in two different modes as described below: 

 

SyncIO: The SyncIO media test creates a random offset for a partition from which the media testing starts. Starting from this offset, the read (Readonly mode) or the write/read (WriteRead mode) begins in a sequential fashion. The test continues until the specified percentage of media is covered.  

 

AsyncIO: The AsyncIO media test always starts from the first block of the partition under test and covers the area specified by the Media Coverage percentage.  

 

AsyncIO uses the read/write feature of the Solaris disk driver to exercise the disk. In Readonly mode, the test sends a maximum of four asynchronous read packets, each with a random size and a random offset into the selected partition. The test then waits for all outstanding I/O activity to complete before issuing another round of packets. This process continues until the whole area is tested. In WriteRead mode, one write packet is issued in every four read packets as a spot check of the write operation. Before data is written to a particular location, data is backed up, write-verified, and restored to its original state. 

File System subtest 

Verifies the disk system's integrity. The File System subtest exercises the partition being tested to determine if it is mounted. If the partition is not already mounted or pre-mounted, then the test is blocked. The test opens two temporary files (of the size specified on File System File Size) and performs a Read/Write test.