[Bug 18921] New: O(n) hash_table_add causes winedbg to take 20 minutes to dump stack when chromium crashes
http://bugs.winehq.org/show_bug.cgi?id=18921 Summary: O(n) hash_table_add causes winedbg to take 20 minutes to dump stack when chromium crashes Product: Wine Version: 1.1.23 Platform: PC OS/Version: Linux Status: NEW Severity: normal Priority: P2 Component: dbghelp AssignedTo: wine-bugs(a)winehq.org ReportedBy: dank(a)kegel.com CC: eric.pouech(a)orange.fr In bug 15206, I mentioned that windbg was too slow to be usable. I ran oprofile while winedbg was churning, and the time appears to all be spent on one line of code in dlls/dbghelp/storage.c: void hash_table_add(struct hash_table* ht, struct hash_table_elt* elt) { ... 569217 89.8978 : for (p = &ht->buckets[hash]; *p; p = &((*p)->next)); Looks like we need to modify struct hash_table and some of its operators to allow a more efficient append operation there. Fixing this bug will be one more step towards being friendly to developers who use Visual Studio and expect our tools to be able to handle .pdb files well. -- Configure bugmail: http://bugs.winehq.org/userprefs.cgi?tab=email Do not reply to this email, post in Bugzilla using the above URL to reply. ------- You are receiving this mail because: ------- You are watching all bug changes.
http://bugs.winehq.org/show_bug.cgi?id=18921 --- Comment #1 from Henri Verbeet <hverbeet(a)gmail.com> 2009-06-13 05:48:22 --- Replacing the list with a standard Wine list should already make the insert less expensive, since you can just add to the tail. Large tables will still degenerate into linked lists though, since as far as I can see the table is never resized. If duplicate symbols could be handled in a different way (e.g. storing them as a list in a single entry), the RB-tree in include/wine/rbtree.h could be used. -- Configure bugmail: http://bugs.winehq.org/userprefs.cgi?tab=email Do not reply to this email, post in Bugzilla using the above URL to reply. ------- You are receiving this mail because: ------- You are watching all bug changes.
http://bugs.winehq.org/show_bug.cgi?id=18921 --- Comment #2 from Eric Pouech <eric.pouech(a)orange.fr> 2009-06-13 08:12:04 --- we're eating lots of memory with loading at once all the symbols using a wine list would add an extra pointer I'd suggest simply keeping a pointer to the last object in the bucket, that would be sufficient regarding Henri's comment, we could have several symbols with same names (static vars in different compilation units for example), but never same name & same address... it just requires (famous last words) to adapt the comparison function A+ -- Configure bugmail: http://bugs.winehq.org/userprefs.cgi?tab=email Do not reply to this email, post in Bugzilla using the above URL to reply. ------- You are receiving this mail because: ------- You are watching all bug changes.
http://bugs.winehq.org/show_bug.cgi?id=18921 --- Comment #3 from Dan Kegel <dank(a)kegel.com> 2009-06-14 12:06:10 --- Eric has a patch that solves this particular bottleneck and gets the time down from 20 minutes to 6 minutes. The next bottleneck, he says, has to do with the fact that we sort the symbol table on every insert rather than in batches. -- Configure bugmail: http://bugs.winehq.org/userprefs.cgi?tab=email Do not reply to this email, post in Bugzilla using the above URL to reply. ------- You are receiving this mail because: ------- You are watching all bug changes.
http://bugs.winehq.org/show_bug.cgi?id=18921 --- Comment #4 from Eric Pouech <eric.pouech(a)orange.fr> 2009-06-27 01:01:43 --- improvement as of #3 has been committed to git likely another 70% improvement -- Configure bugmail: http://bugs.winehq.org/userprefs.cgi?tab=email Do not reply to this email, post in Bugzilla using the above URL to reply. ------- You are receiving this mail because: ------- You are watching all bug changes.
http://bugs.winehq.org/show_bug.cgi?id=18921 Dan Kegel <dank(a)kegel.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |RESOLVED Resolution| |FIXED --- Comment #5 from Dan Kegel <dank(a)kegel.com> 2009-10-05 13:33:44 --- Fixed well enough for now. I'll file another bug next time I hit a performance problem here. -- Configure bugmail: http://bugs.winehq.org/userprefs.cgi?tab=email Do not reply to this email, post in Bugzilla using the above URL to reply. ------- You are receiving this mail because: ------- You are watching all bug changes.
http://bugs.winehq.org/show_bug.cgi?id=18921 Alexandre Julliard <julliard(a)winehq.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|RESOLVED |CLOSED --- Comment #6 from Alexandre Julliard <julliard(a)winehq.org> 2009-10-09 11:14:11 --- Closing bugs fixed in 1.1.31. -- Configure bugmail: http://bugs.winehq.org/userprefs.cgi?tab=email Do not reply to this email, post in Bugzilla using the above URL to reply. ------- You are receiving this mail because: ------- You are watching all bug changes.
participants (1)
-
wine-bugs＠winehq.org