17097 2008-01-30 11:38:02 -0800 CGFontRefs (and HFONTs on Windows) leak because FontCache grows without bound 2008-07-25 12:12:11 -0700 1 1 1 Unclassified WebKit Text 528+ (Nightly build) All All RESOLVED FIXED InRadar P2 Normal --- 1 aroben mitz eric hyatt mitz oldest_to_newest 68816 0 aroben 2008-01-30 11:38:02 -0800 The FontCache currently grows without bound, which means we're leaking the CGFontRefs and HFONTs used to construct the FontPlatformData objects held by the cache. 68818 1 aroben 2008-01-30 11:39:03 -0800 Some quotes from Hyatt on this issue: <dhyatt> it's not obvious how to change it without hurting perf <dhyatt> the tentative idea i had was to refcount FontDatas <dhyatt> and just pretend like FontPlatformData is always a "temporary" <dhyatt> to avoid massive refcount churn on the fontplatformdata <dhyatt> if you look at fontdata's destructor <dhyatt> (i guess simplefontdata now) <dhyatt> it does actually have code to delete the HFONT and release the cgfontref <dhyatt> it never gets called <dhyatt> i just mean i wrote the code assuming that someday the fontdatas would get destroyed <dhyatt> purged from the cache etc 68820 2 aroben 2008-01-30 11:39:44 -0800 <rdar://problem/5715471> 76115 3 mitz 2008-04-01 19:25:00 -0700 *** Bug 18263 has been marked as a duplicate of this bug. *** 76119 4 eric 2008-04-01 22:35:52 -0700 This doesn't matter much on OS X (I don't think). But on Windows, there are only 65k GDI Object Handles per user session. These handle "leaks" can end up causing Safari to take up an unfair number of handles. 76123 5 mitz 2008-04-01 23:04:31 -0700 The HFONTs are now owned by the FontPlatformData (not the SimpleFontData). One possible solution would be to have a way to invalidate those and make the SimpleFontData check the validity before any other accees. You'll also need a way to regenerate the FontPlatformData if they were invalidated (you need a FontDescription and a family name for that IIRC). 80222 6 mitz 2008-05-12 14:07:47 -0700 Fixed in <http://trac.webkit.org/changeset/33056>. 82024 7 mitz 2008-05-31 00:57:39 -0700 The bug is not fixed in TOT. PlatformFontData objects which hold on to HFONTs and CGFontRefs are still held indefinitely by the FontPlatformDataCache. 86948 8 mitz 2008-07-25 12:12:11 -0700 <http://trac.webkit.org/changeset/35352>.