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[Bug testsuite/11514] nd_syscall.exp takes more than 10 times longer than syscall.exp testcase


------- Additional Comments From mjw at redhat dot com  2010-04-20 14:55 -------
(In reply to comment #8)
> (In reply to comment #7)
> > Resolving them all in one go with kallsyms_on_each_symbol() just before
> > registering then in kprobe_derived_probe_group::emit_module_init() seems the
> > quickest way to speed this up.
> 
> Frank correctly pointed out on irc that this isn't a speedup, but jus flips the
> comparison loop inside out. We still need to compare all kallsyms symbols
> against all kprobe symbol names. So we still end up with O(N*M) comparisons. So
> to speed up we really need to be using more clever data structures.

Except that most time seems to go into kallsyms_expand_symbol to uncompress the
kernel symbol table. So flipping the comparison loop inside out to only do that
once might still be a win.

-- 


http://sourceware.org/bugzilla/show_bug.cgi?id=11514

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