[Bug other/10944] alloc_page in ggc-page.c is slow

[steven at gcc dot gnu dot org]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=10944


steven at gcc dot gnu dot org changed:

           What    |Removed                     |Added
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   Last reconfirmed|2003-06-01 18:58:30         |2003-10-13 14:37:14
               date|                            |


------- Additional Comments From steven at gcc dot gnu dot org  2003-10-13 14:37 -------
The new patch implements suggestion 1 from last nights list.

Andrew, you identified the loop over free_pages as a time consumer, but now that
it is gone, I get virtually no measurable time improvements (10ths of seconds on
>1min total compilation time) for the test case for PR8361.  Which (not
surprisingly) once again shows that GC is slow because with each call
ggc_collect we need to do more and more marking...

Are you absolutely, positively sure that this loop is a performance hog? 
Perhaps you can try the patch, it bootstrappes (c,objc,c++) and showed no
regressions on i686.  So far I haven't found convincing evidence that it
improves performance significantly except for the most pathological (artificial)
cases.

Sigh, back to waiting for a new GC strategy...