Re: Huge compile time & run time performance regression 3.3 -> HEAD

[Gabriel Dos Reis <gdr at integrable-solutions dot net>]

Richard Guenther <rguenth@tat.physik.uni-tuebingen.de> writes:

| On 19 May 2003, Gabriel Dos Reis wrote:
| 
| > Richard Guenther <rguenth@tat.physik.uni-tuebingen.de> writes:
| >
| > | > Do you see any compile time regressions at -O0?
| > | >
| > | > (I'm asking for the obvious reason: trying to find out how much work we
| > | > need to do in the front end as opposed to the back end.)
| > |
| > | After killing all forced inlining, I get almost the same timings from 3.3
| > | and 3.4, namely 42.50 and 44.89 seconds.
| > |
| > | Slowdown comes from
| > |
| > | 3.3: name lookup           :   6.92 (17%) usr   0.90 (43%) sys   7.50
| > | (18%) wall
| > | 3.4: name lookup           :   9.06 (22%) usr   0.81 (39%) sys  10.29
| > | (23%) wall
| >
| > I've also noticed that name lookup time has increased from 3.3 to 3.4,
| > probably mostly because now we're doing things more correctly and
| > partly because we didn't really take care to optimize it.  It would be
| > interesting if you could report numbers for name lookup for 3.4:
| >
| >   * before I applied the name lookup
| >   * after I applied it (i.e. cvs as of this moment)
| >
| > What I've noted (and I posted figures) wkas that the patch I applied
| > cut the name lookup time about half on mainline, whereas I got at
| > least 20%  on branch.
| 
| If you mean
| 
| 2003-05-18  Gabriel Dos Reis  <gdr@integrable-solutions.net>
| 
|         * cp-tree.h (struct lang_type_class): Replace data member tags
|         with hash-table nested_udts.
|         (CLASSTYPE_NESTED_UTDS): Rename from CLASSTYPE_TAGS.
|         [...]
| 
| this is already included in the numbers. I.e. the 3.4 numbers are from CVS
| about 2 hours ago.

Thanks.  Do you have numbers for say, mainline as of yesterday?

-- Gaby