C H A P T E R 11 - Data Translation Look-aside Buffer (dtlbtest)

C H A P T E R 11

Data Translation Look-aside Buffer Test (dtlbtest)

The dtlbtest verifies the proper functioning of DTLBs, but it does not measure performance of DTLBs.

Note - dtlbtest does support x86 platforms on Solaris.

This test verifies the following function of DTLBs:

1. Hit/miss tests: Stress DTLBs by generating large numbers of TLB hits and misses.

2. Address Pattern tests: Verify DTLBs correctly translate virtual addresses to physical addresses with stressful address patterns.

dtlbtest detects the installed CPU type and handles it's architectures in full extent.

dtlbtest is classified as an exclusive SunVTS test as its accuracy and coverage depends significantly on the system's background quietness. For the best result, avoid performing any other SunVTS tests in the background, and also disable all user processes and nonessential daemons.

dtlbtest Options

To reach the dialog box below, select the exclusive test mode and right-click on the test name in the System Map and select Test Parameter Options. If you do not see this test in the System Map, you might need to expand the collapsed groups, or your system may not include the device appropriate to this test. Refer to the SunVTS User's Guide for more details.

FIGURE 11-1 dtlbtest Test Parameter Options Dialog Box


Option	Description
Processor ID	Specifies the CPU Id for testing. The default value is all.
Test Type	Specifies the type of test need to be performed. Test type: Hit/miss and address pattern or both. The default value is both.
Page Size	Specifies the DTLB page size to test. The default value is all. Possible page size value: 8k, 64k, 512K, 4M.
Address Pattern loop count	Specifies the address pattern loop count. The default value is 1. loop count value ranges between 1 and 1000.
Address pattern seed value	Specifies the address pattern seed value. The default value is 0 i.e timestamp.


Test Mode	Description
Exclusive	Performs only the dtlbtest (full test).

dtlbtest Command-Line Syntax

/opt/SUNWvts/bin/sparcv9/dtlbtest [-scruvdtlxnf] [-p n] [-i n] [-w n] [-o cpu=N, test=x, psize=x, aloop=n, aseed=n ]


Argument	Description
cpu=cpuid	Specifies the cpuId. The default value is all. cpuid={0.....1023\|all}.
test=testType	Specifies the type of test. The default value is both. testType={h\|a\|both}.
psize=pageSize	Specifies the page size to be tested. The default value is all. pageSize={8K\|64K\|512K\|4M\|all}.
aloop=loopCount	Specifies the address pattern loop count. The default value is 1. loopCount={1 .... 1000}.
aseed=seedValue	Specifies the address pattern seed value. The default value is 0.