571167 - quiet pldhash

Status: RESOLVED DUPLICATE of bug 1058335

(Core :: General, defect)

Description

[Timothy Nikkel (:tnikkel)]

pldhash generates a lot of output in debug builds of the form:

pldhash: for the table at address 0x7f826364ac90, the given entrySize of 112 probably favors chaining over double hashing.

It potentially obscures more useful information. Are these warnings useful to a significant number of people? Can we turn them off?

Comment 1

[Boris Zbarsky [:bzbarsky]]

I believe that if the warning appears that means that you're using the wrong hashtable for the job...

Comment 2

[Brendan Eich [:brendan]]

Timothy, can you stop in a debuger at the line that warns and report the stack backtrace here? Thanks,

/be

Comment 3

[Joshua Cranmer [:jcranmer]]

First one I see:
#0  PL_DHashTableInit (table=0xb2070f88, ops=0xb22f2ec0, data=0x0, 
    entrySize=48, capacity=16) at pldhash.c:241
#1  0xb229e1a0 in nsDocLoader (this=0xb2070f20)
    at /home/source/trunk/mozilla/uriloader/base/nsDocLoader.cpp:175
#2  0xb22654c3 in nsDocShell (this=0xb2070f20)
    at /home/source/trunk/mozilla/docshell/base/nsDocShell.cpp:705
#3  0xb2241863 in nsDocShellConstructor (aOuter=0x0, aIID=..., 
    aResult=0xbfffea10)
    at /home/source/trunk/mozilla/docshell/build/nsDocShellModule.cpp:103
#4  0xb7c35956 in nsGenericFactory::CreateInstance (this=0xb0b24b60, 
    aOuter=0x0, aIID=..., aResult=0xbfffea10) at nsGenericFactory.cpp:80
#5  0xb7c9f538 in nsComponentManagerImpl::CreateInstanceByContractID (
    this=0xb6c73220, aContractID=0xb219d1ce "@mozilla.org/docshell;1", 
    aDelegate=0x0, aIID=..., aResult=0xbfffea10)
    at /home/source/trunk/mozilla/xpcom/components/nsComponentManager.cpp:1712
#6  0xb7c2654a in CallCreateInstance (
    aContractID=0xb219d1ce "@mozilla.org/docshell;1", aDelegate=0x0, aIID=..., 
    aResult=0xbfffea10) at nsComponentManagerUtils.cpp:170
#7  0xb7c26597 in nsCreateInstanceByContractID::operator() (this=0xbfffeb84, 
    aIID=..., aInstancePtr=0xbfffea10) at nsComponentManagerUtils.cpp:210
#8  0xb2193d45 in nsCOMPtr<nsIDocShell>::assign_from_helper (this=0xb6ca8eec, 
    helper=..., aIID=...) at ../../../dist/include/nsCOMPtr.h:1249
#9  0xb2194fb8 in nsCOMPtr<nsIDocShell>::operator= (this=0xb6ca8eec, rhs=...)
#10 0xb21922f8 in nsWebShellWindow::Initialize (this=0xb6ca8ec0, aParent=0x0, 
    aOpener=0x0, aShell=0xb16bdab0, aUrl=0xb6c19240, aInitialWidth=100, 
    aInitialHeight=100, aIsHiddenWindow=1, widgetInitData=...)
    at /home/source/trunk/mozilla/xpfe/appshell/src/nsWebShellWindow.cpp:216
#11 0xb218c604 in nsAppShellService::JustCreateTopWindow (this=0xb0b52780, 
    aParent=0x0, aUrl=0xb6c19240, aChromeMask=4094, aInitialWidth=100, 
    aInitialHeight=100, aIsHiddenWindow=1, aAppShell=0xb16bdab0, 
    aResult=0xbfffed10)
    at /home/source/trunk/mozilla/xpfe/appshell/src/nsAppShellService.cpp:391
#12 0xb218cfed in nsAppShellService::CreateHiddenWindow (this=0xb0b52780, 
    aAppShell=0xb16bdab0)
    at /home/source/trunk/mozilla/xpfe/appshell/src/nsAppShellService.cpp:182
#13 0xb1f84b06 in nsAppStartup::CreateHiddenWindow (this=0xb0dd3c10)
    at /home/source/trunk/mozilla/toolkit/components/startup/src/nsAppStartup.cpp:161
#14 0xb7d3fa2c in XRE_main (argc=2, argv=0xbffff2d4, aAppData=0xb6c0e380)
    at /home/source/trunk/mozilla/toolkit/xre/nsAppRunner.cpp:3547
#15 0x080496ae in main (argc=2, argv=0xbffff2d4)
    at /home/source/trunk/mail/app/nsMailApp.cpp:101

Another one with the same tip; then I get:
#0  PL_DHashTableInit (table=0xb0d41190, ops=0xb26da720, data=0x0, 
    entrySize=48, capacity=16) at pldhash.c:241
#1  0xb26d292f in nsTHashtable<nsHostEntry>::Init (this=0xb0d41190, 
    initSize=16) at ../../dist/include/nsTHashtable.h:348
#2  0xb26ce009 in nsPermissionManager::Init (this=0xb0d41160)
    at /home/source/trunk/mozilla/extensions/cookie/nsPermissionManager.cpp:121
#3  0xb26c9594 in nsPermissionManagerConstructor (aOuter=0x0, aIID=..., 
    aResult=0xbfffddd0)
    at /home/source/trunk/mozilla/extensions/cookie/nsCookieModule.cpp:50

More nsDocLoader complaints, then:
#0  PL_DHashTableInit (table=0xb209d898, ops=0xb1dfea60, data=0x0, 
    entrySize=52, capacity=16) at pldhash.c:241
#1  0xb1d5de6f in nsTHashtable<nsClientAuthRememberEntry>::Init (
    this=0xb209d898, initSize=16)
    at ../../../../dist/include/nsTHashtable.h:348
#2  0xb1d5d26f in nsClientAuthRememberService::Init (this=0xb209d880)
    at /home/source/trunk/mozilla/security/manager/ssl/src/nsClientAuthRemember.cpp:80
#3  0xb1d75115 in nsNSSComponent::Init (this=0xaa27cf00)
    at /home/source/trunk/mozilla/security/manager/ssl/src/nsNSSComponent.cpp:1889
#4  0xb1d8e723 in nsNSSComponentConstructor (aOuter=0x0, aIID=..., 
    aResult=0xbfffa8b4)
    at /home/source/trunk/mozilla/security/manager/ssl/src/nsNSSModule.cpp:184

And then I see the window; after another nsDocLoader complaint, I shut the window down and that it was it.

Comment 4

[Timothy Nikkel (:tnikkel)]

One more:

#0  PL_DHashTableInit (table=0x7f625d75dff0, ops=0x7f627cce5690, data=0x0, entrySize=112, capacity=16)
    at pldhash.c:241
#1  0x00007f627be60b40 in nsTHashtable<nsCertOverrideEntry>::Init(unsigned int) () from ./libxul.so
#2  0x00007f627be60209 in nsCertOverrideService::Init (this=0x7f625d75dfb0)
    at ../../../../../security/manager/ssl/src/nsCertOverrideService.cpp:135
#3  0x00007f627be7b7f1 in nsCertOverrideServiceConstructor (aOuter=<value optimized out>, aIID=..., 
    aResult=0x7fff46c2f560) at ../../../../../security/manager/ssl/src/nsNSSModule.cpp:220
#4  0x00007f627c18600c in nsComponentManagerImpl::CreateInstance (this=<value optimized out>, 
    aClass=..., aDelegate=0x0, aIID=..., aResult=0x7fff46c2f560)
    at ../../../xpcom/components/nsComponentManager.cpp:1622
#5  0x00007f627c18b75f in nsComponentManagerImpl::GetService (this=0x7f626ca26160, aClass=..., 
    aIID=<value optimized out>, result=0x7fff46c2f630)
    at ../../../xpcom/components/nsComponentManager.cpp:1931

Comment 5

[timeless]

i think comment 4 is bug 455391 filed by bz...

Comment 6

[Robert O'Callahan (:roc) (email my personal email if necessary)]

So you're saying that for objects reporting this warning, the hash entries should be pointers to malloced memory instead of the data itself?

Comment 7

[Boris Zbarsky [:bzbarsky]]

If the goal is to have a hashtable using as little memory as possible, yes....  Which is a bit of an "if".

Comment 8

[Jesse Ruderman]

http://hg.mozilla.org/mozilla-central/rev/d0342ebb5766 from khuey should help:

"Shut pldhash up for the 'probably' case."

Comment 9

[Nicholas Nethercote [inactive]]

BookmarkKeyClass, in toolkit/components/places/nsNavBookmarks.h, causes one of these warnings at start-up.

Comment 10

[Marco Bonardo [:mak]]

(In reply to Nicholas Nethercote [:njn] from comment #9)
> BookmarkKeyClass, in toolkit/components/places/nsNavBookmarks.h, causes one
> of these warnings at start-up.

That was killed recently.

Comment 11

[Nicholas Nethercote [inactive]]

Oh, I removed the warning in bug 1058335.