135505 - Performance - unnecessary calls to see if protocol handler exists

Status: VERIFIED FIXED

(SeaMonkey :: General, defect, P3)

Description

[Mike Kaply [:mkaply]]

During startup, we repeatdly call:

http://lxr.mozilla.org/seamonkey/source/uriloader/exthandler/win/nsOSHelperAppSe
rvice.cpp#176

for the rdf protocol.

On Windows, this is a registry hit every time.

Maybe we should shortcircuit RDF or something.

Comment 1

[Mike Kaply [:mkaply]]

Copying a couple people.

Not including sidebar, there are 39 calls to this function during startup, all 
passing rdf.

Comment 2

[Alec Flett]

damn! we could at least cache the result!
can you post a sample stack trace of one of the 39 hits to this check?

Comment 3

[Mike Kaply [:mkaply]]

 Function                                                                      
                      | Part                      
------------------------------------------------------------------------------------------------------+---------------------------
 nsOSHelperAppService::ExternalProtocolHandlerExists(const char*,int*)         
                      | NSOSHELPERAPPSERVICE      
 nsExternalProtocolHandler::HaveProtocolHandler(nsIURI*)                       
                      | NSEXTERNALPROTOCOLHANDLER 
 nsExternalProtocolHandler::NewURI(const nsACString&,const
char*,nsIURI*,nsIURI**)                    | NSEXTERNALPROTOCOLHANDLER 
 nsIOService::NewURI(const nsACString&,const char*,nsIURI*,nsIURI**)           
                      | NSIOSERVICE               
 NS_NewURI(nsIURI**,const nsACString&,const char*,nsIURI*,nsIIOService*)       
                      | NSRDFSERVICE              
 RDFServiceImpl::GetDataSource(const char*,int,nsIRDFDataSource**)             
                      | NSRDFSERVICE              
 RDFServiceImpl::GetDataSource(const char*,nsIRDFDataSource**)                 
                      | NSRDFSERVICE              
 nsXULTemplateBuilder::LoadDataSources()                                       
                      | NSXULTEMPLATEBUILDER      
 nsXULTemplateBuilder::Init(nsIContent*)                                       
                      | NSXULTEMPLATEBUILDER      
 nsXULDocument::CheckTemplateBuilder(nsIContent*)                              
                      | NSXULDOCUMENT             
 nsXULDocument::AddElementToDocumentPost(nsIContent*)                          
                      | NSXULDOCUMENT             
 nsXULDocument::ResumeWalk()                                                   
                      | NSXULDOCUMENT             
 nsXULDocument::EndLoad()                                                      
                      | NSXULDOCUMENT             
 XULContentSinkImpl::DidBuildModel(int)                                        
                      | NSXULCONTENTSINK          
 nsExpatDriver::DidBuildModel(unsigned int,int,nsIParser*,nsIContentSink*)     
                      | NSEXPATDRIVER.OBJ         
 nsParser::DidBuildModel(unsigned int)                                         
                      | NSPARSER.OBJ              
 nsParser::ResumeParse(int,int,int)                                            
                      | NSPARSER.OBJ              
 nsParser::ContinueParsing()                                                   
                      | NSPARSER.OBJ              
 CSSLoaderImpl::Cleanup(URLKey&,SheetLoadData*)                                
                      | NSCSSLOADER               
 CSSLoaderImpl::SheetComplete(nsICSSStyleSheet*,SheetLoadData*)                
                      | NSCSSLOADER               
 CSSLoaderImpl::Cleanup(URLKey&,SheetLoadData*)                                
                      | NSCSSLOADER               
 CSSLoaderImpl::SheetComplete(nsICSSStyleSheet*,SheetLoadData*)                
                      | NSCSSLOADER               
 CSSLoaderImpl::Cleanup(URLKey&,SheetLoadData*)                                
                      | NSCSSLOADER               
 CSSLoaderImpl::SheetComplete(nsICSSStyleSheet*,SheetLoadData*)                
                      | NSCSSLOADER               
 CSSLoaderImpl::ParseSheet(nsIUnicharInputStream*,SheetLoadData*,int&,nsICSSStyleSheet*&)             | NSCSSLOADER               
 CSSLoaderImpl::DidLoadStyle(nsIStreamLoader*,nsString*,SheetLoadData*,unsigned
int)                  | NSCSSLOADER               
 SheetLoadData::OnStreamComplete(nsIStreamLoader*,nsISupports*,unsigned
int,unsigned int,const char*) | NSCSSLOADER               
 nsStreamLoader::OnStopRequest(nsIRequest*,nsISupports*,unsigned int)          
                      | NSSTREAMLOADER            
 nsJARChannel::OnStopRequest(nsIRequest*,nsISupports*,unsigned int)            
                      | NSJARCHANNEL              
 nsOnStopRequestEvent::HandleEvent()                                           
                      | NSREQUESTOBSERVERPROXY    
 nsARequestObserverEvent::HandlePLEvent(PLEvent*)                              
                      | NSREQUESTOBSERVERPROXY    
 PL_HandleEvent                                                                
                      | PLEVENT                   
 PL_ProcessPendingEvents                                                       
                      | PLEVENT                   
 _md_EventReceiverProc                                                         
                      | PLEVENT                   
 0x1E935800                                                                    
                      | PMMERGE.DLL:4             
 nsAppShell::Run()                                                             
                      | NSAPPSHELL.OBJ            
 nsAppShellService::Run()                                                      
                      | NSAPPSHELLSERVICE.OBJ     
 main1(int,char**,nsISupports*)                                                
                      | NSAPPRUNNER.OBJ           
 main                                                                          
                      | NSAPPRUNNER.OBJ           
 _start                                                                        
                      | EXESTRTI                  
 0x1C04C183                                                                    
                      | DOSCALL1.DLL:4            

Comment 4

[Chris Waterson]

Attachment: possible fix

Per mkaply's suggestion. alecf, if you think it would be better to cache
failure at a lower level, let's do that instead.

Comment 5

[Alec Flett]

Comment on attachment 77769 [details] [diff] [review]
possible fix

nope, I think this is just dandy. A one-line comment explaining why you're
excluding "rdf:" would be my only request
sr=alecf with that

Comment 6

[Chris Waterson]

rjc, tingley: r=? (I'll add the comment that alecf suggests...)

Comment 7

[Robert John Churchill]

Comment on attachment 77769 [details] [diff] [review]
possible fix

r=rjc

Comment 8

[Randell Jesup [:jesup] (needinfo me)]

Comment on attachment 77769 [details] [diff] [review]
possible fix

a=[e-mail]
I'd like to see the explanatory comment added when it's checked in too.

Comment 9

[Chris Waterson]

Fix checked in, with explanatory comment.

Comment 10

[Mike Kaply [:mkaply]]

verified. I don't see this anymore.