-----Original Message-----
> > (BTW, at a glance I'm not sure why the 2nd stage is needed...
> > sp_hashed was already checked with STREQ in symname_hash_search if found,
> > otherwise st->synmane_hash should include all kernel symbols..)
> >
> Hello Kazu,
>
> Yes, from my view I also think the 2nd stage is not necessary, I have
> thought about removing
> it as well, but I just don't want to go too far at one step. :-)
OK, I see.
> > One more, do you have any slow command that will be especially improved
> > by the patch? I'm ok with the sym command taking 3ms :-)
> > I'd like to know why the patch should be applied or how much the worst
> > command etc. will be improved, to see the importance of it.
> >
>
> No, I don't have a specific slow command. Because the modified functions
> symbol_search and symbol_exists are fundamental and widely used by
> other crash functions, thus the benefit of performance improvement can
> get accumulated. In addition, the time consumption for T3 shortened greatly,
> from 2.4 to 0.017, maybe this can be one of the reasons.
OK.
As far as I've checked a large machine (with 192 CPUs), there are not many
commands but several commands call symbol_search and symbol_exists returning
"not found" many times:
symbol_search symbol_exists
found NULL found NULL
startup 95 21 29 21
ps -m 1951 1951 0 0
irq 1850 0 0 13448
irq -a 1850 0 884 10777
irq -s 1850 0 884 10777
timer 193 193 0 0
Actually, these commands were obviously improved by the patch.
So let's add some explanation like this to the commit log:
" symbol_search and symbol_exists are fundamental and widely used by
other crash functions, thus the benefit of performance improvement can
get accumulated. For example, "ps -m" and "irq" commands, which call
the functions many times, will become faster with the patch."
Anyway, I'll review the patch, please wait for a while.
Thanks,
Kazu
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