Virtual Memory Test (vmem)

This test checks virtual memory; that is, it tests the combination of physical memory and the swap partitions of the disk(s).

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Note - This test may not stop immediately after being disabled.

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This test uses the Solaris valloc (page aligned) system call to allocate, write, read, and compare virtual memory. These operations normally cause heavy paging activity on the system and simulates a stressful environment for the operating system. This test also detects ECC parity errors, memory read errors, addressing problems, and displays the corresponding virtual memory addresses on failure.

Swap Space Consideration

Running this test puts a significant burden on the operating system, since it uses the majority of swap space available for testing. You should use the swap space reserve option to vmem when non-SunVTS test processes are started after SunVTS testing has started. See Swap Space Requirements in the SunVTS 2.0 User's Guide for a complete discussion of swap space requirements.

vmem Options

Figure 32-1 vmem

vmem Configuration The amount of memory listed in the configuration field is equivalent to the sum of the used and available swap space amounts returned by the swap -s command. It indicates the amount of virtual memory found, rounded up to the nearest Kbyte.

Test Amount An amount can be specified to test the virtual memory, instead of the default. Specifying a number greater than the available memory, can cause vmem or other running tests to fail.

Mode There are two modes available:

Page mode tests assigned virtual memory one page at a time. Each page is mapped to the temporary file /tmp/vmem.page and then it is paged out to storage after the data is written. Next, the page is paged in before being read and compared.

Stress mode allocates (valloc) the entire assigned memory from the system, writing from beginning to end. Then the memory is read back and compared with the original pattern, one long word at a time.

In regular mode, the amount to be tested is limited by the physical memory size.

Reserve The reserve option specifies the amount of memory to reserve from being tested by vmem. The reserved space is used for other processes running concurrently with the or SunVTS tests. The reserve option can be used to reserve memory in addition to the default. This option applies only to a specific instance. Trying to reserve more memory than was assigned to be tested by this instance, will cause the test to fail.

vmem Test Modes

Connectivity Mode Not applicable for vmem.

Online Mode Not applicable for vmem.

Offdline Mode In this mode, vmem test writes a pattern to an amount of virtual memory specified by the user. Then the data is read back and compared. If there is a miscompare, the data is read again and compared. Whenever there is a miscompare, the virtual address is reported. When there is a miscompare on recomparison, an attempt is made to convert the virtual address to the physical address if the SunVTS diagnostic driver is installed.

vmem Command Line Syntax

/opt/SUNWvts/bin/vmem standard_arguments -o mode=type, reserve=number,
amount=number, bdinfo=number, cerr=number

Argument	Explanation
mode=type	Specifies which mode of the vmem test you want to run; you can choose between page mode, which tells the write/read memory test to proceed one system memory page at a time, and regular, which valloc's the entire assigned memory which is read and compared, one long word at a time
reserve=number	Specifies the amount of Mbytes of virtual memory to reserve in addition to the default amount
amount=number	Specifies the number of Mbytes of memory to be tested instead of the default amount
bdinfo=number	Provides the board number information for all the CPU/memory boards in the system. For example, if board 0 and board 5 have memory, then the bdinfo=33 (2**5+2**0).
cerr=number	Specifies the maxiumu number of contiguous errors to be dumped when a memory error occurs.

vmem Error Messages

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Note - 6001-6004 and 8001-8010 are fatal errors.

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6001  setrlimit(RLIMIT_DATA) failed to set to
RLIM_INFINITY: <error_message>

Probable_Cause(s):

a. Failed to increase the size of test process' heap to 2GB.

6002  Test terminated after finding maximum number
(<number>) of noncontiguous errors.

6003  msync() failed: <error_message>

Probable_Cause(s):

a. Failed to synchronize memory with physical storage.

6004  Test terminated after finding miscompared data.

Probable_Cause(s):

a. Test failed.

8001  Test completed.  Found %d noncontiguous miscompare
errors.

Probable_Cause(s):

a. Suspect swap partition(s). b. Suspect SCSI controller.

c. Faulty system software.

Recommended_Action(s):

a. Consult your authorized Sun service provider.

8002  Increase swap space to allocate atleast <number> MB
from the process' heap.

Probable_Cause(s):

a. Failed to increase mem process' heap storage.

8003  Attempt to reserve more than what's been assigned.

Recommended_Action(s):

a. Reduce the "reserve" amount.

8004  valloc(<address>) failed: <error_message>

Recommended_Action(s):

a. Increase swap space or reduce the reserve amount.

8005  Open(<file_name>) failed: <error_message>

Probable_Cause(s):

a. Failed to open the file <file_name> used in the "page" mode.

8006  mmap() virtual address <address> to <file_name>
failed: <error_message>

Probable_Cause(s):

a. Failed to map a region at the virtual address of the file <file_name> used in the "page" mode.

8007  munmap(<address>) failed: <error_message>.

Probable_Cause(s):

a. Failed to unmap a region at the virtual address of the file <file_name> used in the "page" mode.

8008  close() failed on <file_name>: <error_message>
8009  Not enough space to store miscompare information.

Probable_Cause(s):

a. Failed to allocate space to store miscompare data.

Recommended_Action(s):

a. Increase swap space or reduce the load on the system.

8010  swapctl() failed: <error_message>

Probable_Cause(s):

a. Failed to obtain the amount of swap space configured in the system.