DAX fallbacks

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Operating Systems Solaris DAX fallbacks

07-26-2018

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DAX fallbacks

Hi,

could you explain what DAX fallbacks mean in detail and how to avoid them? Or is it ok to have fallbacks?

Unfortunately googling does not help...

MANpage says: fallbacks == Number of commands completed by the software, which DAX could not complete

OK, but why and what does it mean for the DB?

Running RAC on M7 with InMemory:

1st node=DAX commands 35.608.411 with 18 fallbacks

2nd node=DAX commands 63.563.607 with 2.656.188 fallbacks

Is it just a bad day for the second node? Any ideas how I could dig deeper at OS or DB level?

Thanks in advance and regards

- Martin

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pegasus-dax-validator

PEGASUS-DAX-VALIDA(1)													     PEGASUS-DAX-VALIDA(1)

NAME

       pegasus-dax-validator - determines if a given DAX file is valid.

SYNOPSIS

       pegasus-dax-validator daxfile [verbose]

DESCRIPTION

       The pegasus-dax-validator is a simple application that determines, if a given DAX file is valid XML. For this, it parses the file with as
       many XML validity checks that the Apache Xerces XML parser framework supports.

OPTIONS

       daxfile
	   The location of the file containing the DAX.

       verbose
	   If any kind of second argument was specified, not limited to the string verbose, the verbose output mode is switched on.

RETURN VALUE

       If the DAX was parsed successfully, or only warning's were issued, the exit code is 0. Any 'error or fatal error will result in an exit
       code of 1.

       Additionally, a summary statistics with counts of warnings, errors, and fatal errors will be displayed.

EXAMPLE

       The following shows the parsing of a DAX file that uses the wrong kind of value for certain enumerations. The output shows the errors with
       the respective line number and column number of the input DAX file, so that one can find and fix them more easily. (The lines in the
       example were broken to fit the manpage format.)

	   $ pegasus-dax-validator bd.dax
	   ERROR in line 14, col 110: cvc-enumeration-valid: Value 'i386' is not
	    facet-valid with respect to enumeration '[x86, x86_64, ppc, ppc_64,
	    ia64, sparcv7, sparcv9, amd64]'. It must be a value from the
	    enumeration.
	   ERROR in line 14, col 110: cvc-attribute.3: The value 'i386' of
	    attribute 'arch' on element 'executable' is not valid with respect to
	    its type, 'ArchitectureType'.
	   ERROR in line 14, col 110: cvc-enumeration-valid: Value 'darwin' is
	    not facet-valid with respect to enumeration '[aix, sunos, linux, macosx,
	    windows]'. It must be a value from the enumeration.
	   ERROR in line 14, col 110: cvc-attribute.3: The value 'darwin' of
	    attribute 'os' on element 'executable' is not valid with respect to
	    its type, 'OSType'.

	   0 warnings, 4 errors, and 0 fatal errors detected.

SEE ALSO

       Apache Xerces-J http://xerces.apache.org/xerces2-j/

AUTHORS

       Jens-S. Vockler <voeckler at isi dot edu>

       Pegasus Team http://pegasus.isi.edu/

								    05/24/2012						     PEGASUS-DAX-VALIDA(1)

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