Re: Trouble with new tracker designator?

Hi Ralf:

In message <[email protected]>,
Ralf Schlatterbeck writes:
>On Tue, Jul 21, 2020 at 11:50:05PM -0400, John P. Rouillard wrote:
>> I did a little performance testing with the various possible re's
>> and a subset of the cases you tested.
>> 
>> Compiling the better re is .9% slower and your best re is 3.6% worse
>> than current.
>> 
>> Matching is 35% worse for the better re and 45% worse for your best
>> re. I don't have good stats on how often splitDesignator is called and
>> how much of an impact a 45% slowdown would cause. Trying to use
>> cProfile and pstats isn't exactly clear.
>
>I don't think that parsing a string of typically max. len 20 or so will
>significantly impact performance.

It looks like permission check in the web interface calls
splitDesignator. Neither splitDesignator nor the calls from
cgi/actions.py:PermCheck::permissions show up in the perf data. So my
conclusion is that you are right and that is not called enough to show
up.

>> Technically _ is not a letter. I wonder if we should keep classes
>> starting with _ in reserve for future use (hidden/internal class for
>> whatever that means).
>
>Yes, especially since roundup re-maps table names to start with an
>underscore, no idea what a double underscore would do but I'd not permit
>names with a starting underscore.

Fair enough. I don't expect that double underscore would be an issue
though.

Now if we represented the table for class _classname as _classname
rather than __classname, I can see that leading to maddness. But that
doesn't appear to be an issue given a quick perusal of backends and
roundupdb.
 
>> However if we properly limit class names in Class::__init__ I wonder
>> if we can simplify the re in splitDesignator assuming that the
>> designator has a classname of initial alpha, alphanumerics (plus _)
>> and no trailing digits. That still leaves us with a 35% slowdown over
>> the current re which doesn't support embedded numbers in classnames
>> 8-(.
>
>Fine with me.
>
>Thanks to Tom for finding this and reporting it!

Yeah that's a wierd one.

>And thanks John for so deeply looking into it.

I have some free time these days so....

Thanks for your thoughts. I appreciate the feedback.

Have a great week.

--
				-- rouilj
John Rouillard
===========================================================================
My employers don't acknowledge my existence much less my opinions.