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Conference decwet::visual

Title:Microsoft Visual C++ bug reports and kits
Notice:Register in Topic 2. 5.Last for latest Kit
Moderator:DECWET::THOMASN
Created:Tue May 17 1994
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:521
Total number of notes:2938

481.0. "kernrate (kernel profiling) problem" by WRKSYS::NISHIMOTO () Fri Mar 14 1997 10:41

	Hello.  I'm doing some kernel profiling and using kernrate
	to determine some "stuff".

	I'm trying to find out why my .dll got a lot slower
	(we added a new version of an internal library and, sure,
	it is the "reason" why the .dll goes slower, but what
	in the new internal library is causing the problem?).

	I'm using kernrate and it looks like it might be able to
	tell me stuff.  However, 25% of my time is spent in `string'.
	And, there is more than on instanace of `string' in the output.

	How can I find out what these `string' references actually
	are?   A lot of my .dll's symbols do show up, and if `string'
	was a lower percentage, I'd ignore it.

	Any hints? 

	Or, should I be using something else?

	Thanks.

		Pete
T.RTitleUserPersonal
Name		DateLines
481.1probably alignment faultsDECWET::PETERSONFri Mar 14 1997 17:4119
    don't know anything about kernel profiling or kernrate, but I'll hazard
    some possibilities:
    
    I think what you said was:
    1. With a new internal library, your dll got much slower
    2. profiling shows lots of time in "string" routine (or routines)
    
    The likeliest problem is that the new internal library has an alignment
    problem.  you can confirm this simple by running perfmon and examining
    the system parameter: "alignment fixups/second"
    
    I suspect you are getting lots of them (over a hundred, but over
    10/second would affect performance)
    
    If you are, you can track down where it is happening by using axpalign
    and using the debugger (but not the beta debuggers) to track down the
    faults one by one.  They would probably be in the new internal
    library's "string" routine
481.2Need informationDECWET::METZGERThu Apr 03 1997 11:101
    Which version on the compiler and which library and dlls are you using?