160491 2016-08-02 23:53:14 -0700 [GTK] Bad performance in accelerated compositing mode with the modesetting intel driver and DRI3 enabled 2018-12-21 16:48:30 -0800 1 1 1 Unclassified WebKit WebKitGTK WebKit Local Build Unspecified Unspecified RESOLVED FIXED https://bugs.freedesktop.org/show_bug.cgi?id=85064 Gtk P2 Normal --- 1 cgarcia webkit-unassigned bugs-noreply clopez jdapena mcatanzaro mrobinson rfarmer84 svillar yoon zan oldest_to_newest 1216822 0 cgarcia 2016-08-02 23:53:14 -0700 This is becoming the default in several linux distributions and it makes WebKitGTK+ unusable in accelerated compositing mode, which is now always enabled because since we switched to use the threaded compositor. The problem seems to be an optimization of the intel driver for windows that are offscreen, and our redirected window is always positioned at ScreenWidth + 1, 0. 1216823 1 285205 cgarcia 2016-08-02 23:59:05 -0700 Created attachment 285205 Patch 1216832 2 svillar 2016-08-03 00:50:07 -0700 I was tempted to r+ but it looks like this is an undesirable side effect, so I'd prefer not to rely on that. From the freedesktop bug: "Weird, not sure why that avoids the problem; maybe there's an off-by-one bug somewhere which causes the window to be incorrectly considered on-screen. I wouldn't recommend relying on that. Also, again I'm not sure that negative coordinates can never be visible." Also "Assuming a window is really the only possibility, (why) can't it set the swap interval to 0 via one of the GLX extensions for this, to prevent SwapBuffers operations from getting throttled?" Can't we do this instead? 1216841 3 cgarcia 2016-08-03 01:10:51 -0700 (In reply to comment #2) > I was tempted to r+ but it looks like this is an undesirable side effect, so > I'd prefer not to rely on that. From the freedesktop bug: > > "Weird, not sure why that avoids the problem; maybe there's an off-by-one > bug somewhere which causes the window to be incorrectly considered > on-screen. I wouldn't recommend relying on that. Also, again I'm not sure > that negative coordinates can never be visible." Yes, but he also said that using WidthOfScreen is bad in any case, so if the patch fixes that and works as a workaround, we could land it in any case and then continue working a better solution, but with a workaround to make WebKitGTK+ usable again. > Also > > "Assuming a window is really the only possibility, (why) can't it set the > swap interval to 0 via one of the GLX extensions for this, to prevent > SwapBuffers operations from getting throttled?" > > Can't we do this instead? I guess, I'm not a graphics expert, and I don't even know if we really need to use a window or not. I'll take a look at the swap interval thing in any case. 1217070 4 mcatanzaro 2016-08-03 12:40:48 -0700 (In reply to comment #3) > Yes, but he also said that using WidthOfScreen is bad in any case True. r=me on that basis, but I recommend giving the upstream bug a couple days to settle before committing, now that the Xorg folks are actively looking into the issue. We also should have an answer to their question as to why we use an offscreen window instead of a pixmap, which is clearly their recommendation. 1217071 5 mcatanzaro 2016-08-03 12:41:51 -0700 CCing folks who might possibly have an answer to the question in comment #4. 1217072 6 mcatanzaro 2016-08-03 12:44:14 -0700 (In reply to comment #2) > I was tempted to r+ but it looks like this is an undesirable side effect, so > I'd prefer not to rely on that. My main concern is that it might be a bug that the negative offset works to avoid throttling. 1217314 7 cgarcia 2016-08-03 21:55:30 -0700 (In reply to comment #6) > (In reply to comment #2) > > I was tempted to r+ but it looks like this is an undesirable side effect, so > > I'd prefer not to rely on that. > > My main concern is that it might be a bug that the negative offset works to > avoid throttling. Right, that's why I don't consider it a fix, if that's actually a bug and is fixed eventually the performance will be bad again, but I'm pretty sure we will not be the only ones affected like now, because most of the code that creates an offscreen window use negative coords, either -1, -1 or -100, -100. 1218458 8 cgarcia 2016-08-07 22:42:25 -0700 Committed r204250: <http://trac.webkit.org/changeset/204250> 1490570 9 rfarmer84 2018-12-21 16:48:30 -0800 I experience bad performance with accelerated compositing mode on using WebkitGTK+ 2.22.5 on Fedora 29 with Intel Iris 540 (Skylake mobile) graphics. Turning it off makes pretty much everything faster, but particularly Facebook, which is nearly unusable with accelerated compositing on. Also, when playing videos or scrolling through a site like Facebook, the laptop becomes hot and the fan goes full blast, which does not happen with accelerated compositing off. Would this bug be the issue I'm experiencing, or should I file a new bug about this? 285205 2016-08-02 23:59:05 -0700 2016-08-03 12:40:56 -0700 Patch wk2-dri3.diff text/plain 1986 cgarcia ZGlmZiAtLWdpdCBhL1NvdXJjZS9XZWJLaXQyL0NoYW5nZUxvZyBiL1NvdXJjZS9XZWJLaXQyL0No YW5nZUxvZwppbmRleCA1Y2NhZGQ2Li4zYzY1MGZjIDEwMDY0NAotLS0gYS9Tb3VyY2UvV2ViS2l0 Mi9DaGFuZ2VMb2cKKysrIGIvU291cmNlL1dlYktpdDIvQ2hhbmdlTG9nCkBAIC0xLDMgKzEsMjAg QEAKKzIwMTYtMDgtMDIgIENhcmxvcyBHYXJjaWEgQ2FtcG9zICA8Y2dhcmNpYUBpZ2FsaWEuY29t PgorCisgICAgICAgIFtHVEtdIEJhZCBwZXJmb3JtYW5jZSBpbiBhY2NlbGVyYXRlZCBjb21wb3Np dGluZyBtb2RlIHdpdGggdGhlIG1vZGVzZXR0aW5nIGludGVsIGRyaXZlciBhbmQgRFJJMyBlbmFi bGVkCisgICAgICAgIGh0dHBzOi8vYnVncy53ZWJraXQub3JnL3Nob3dfYnVnLmNnaT9pZD0xNjA0 OTEKKworICAgICAgICBSZXZpZXdlZCBieSBOT0JPRFkgKE9PUFMhKS4KKworICAgICAgICBUaGlz IGlzIGJlY29taW5nIHRoZSBkZWZhdWx0IGluIHNldmVyYWwgbGludXggZGlzdHJpYnV0aW9ucyBh bmQgaXQgbWFrZXMgV2ViS2l0R1RLKyB1bnVzYWJsZSBpbiBhY2NlbGVyYXRlZAorICAgICAgICBj b21wb3NpdGluZyBtb2RlLCB3aGljaCBpcyBub3cgYWx3YXlzIGVuYWJsZWQgYmVjYXVzZSBzaW5j ZSB3ZSBzd2l0Y2hlZCB0byB1c2UgdGhlIHRocmVhZGVkIGNvbXBvc2l0b3IuIFRoZQorICAgICAg ICBwcm9ibGVtIHNlZW1zIHRvIGJlIGFuIG9wdGltaXphdGlvbiBvZiB0aGUgaW50ZWwgZHJpdmVy IGZvciB3aW5kb3dzIHRoYXQgYXJlIG9mZnNjcmVlbiwgYW5kIG91ciByZWRpcmVjdGVkCisgICAg ICAgIHdpbmRvdyBpcyBhbHdheXMgcG9zaXRpb25lZCBhdCBTY3JlZW5XaWR0aCArIDEsIDAuIFVz aW5nIG5lZ2F0aXZlIGNvb3JkaW5hdGVzIHRvIHBvc2l0aW9uIHRoZSByZWRpcmVjdGVkIHdpbmRv dworICAgICAgICBvZmZzY3JlZW4gZml4ZXMgdGhlIHByb2JsZW0uCisgICAgICAgIFNlZSBhbHNv IGh0dHBzOi8vYnVncy5mcmVlZGVza3RvcC5vcmcvc2hvd19idWcuY2dpP2lkPTg1MDY0LgorCisg ICAgICAgICogV2ViUHJvY2Vzcy9XZWJQYWdlL2d0ay9SZWRpcmVjdGVkWENvbXBvc2l0ZVdpbmRv dy5jcHA6CisgICAgICAgIChXZWJLaXQ6OlJlZGlyZWN0ZWRYQ29tcG9zaXRlV2luZG93OjpSZWRp cmVjdGVkWENvbXBvc2l0ZVdpbmRvdyk6IFBvc2l0aW9uIHRoZSBwYXJlbnQgd2luZG93IGF0IC0x LCAtMS4KKwogMjAxNi0wOC0wMSAgQ2FybG9zIEdhcmNpYSBDYW1wb3MgIDxjZ2FyY2lhQGlnYWxp YS5jb20+CiAKICAgICAgICAgW0dUS10gTW92ZSB0aGUgcmVkaXJlY3RlZCBYQ29tcG9zaXRlIHdp bmRvdyB0byB0aGUgd2ViIHByb2Nlc3MKZGlmZiAtLWdpdCBhL1NvdXJjZS9XZWJLaXQyL1dlYlBy b2Nlc3MvV2ViUGFnZS9ndGsvUmVkaXJlY3RlZFhDb21wb3NpdGVXaW5kb3cuY3BwIGIvU291cmNl L1dlYktpdDIvV2ViUHJvY2Vzcy9XZWJQYWdlL2d0ay9SZWRpcmVjdGVkWENvbXBvc2l0ZVdpbmRv dy5jcHAKaW5kZXggMWNmZDhiNy4uZGIzMmFlMiAxMDA2NDQKLS0tIGEvU291cmNlL1dlYktpdDIv V2ViUHJvY2Vzcy9XZWJQYWdlL2d0ay9SZWRpcmVjdGVkWENvbXBvc2l0ZVdpbmRvdy5jcHAKKysr IGIvU291cmNlL1dlYktpdDIvV2ViUHJvY2Vzcy9XZWJQYWdlL2d0ay9SZWRpcmVjdGVkWENvbXBv c2l0ZVdpbmRvdy5jcHAKQEAgLTcyLDcgKzcyLDcgQEAgUmVkaXJlY3RlZFhDb21wb3NpdGVXaW5k b3c6OlJlZGlyZWN0ZWRYQ29tcG9zaXRlV2luZG93KFdlYlBhZ2UmIHdlYlBhZ2UpCiAKICAgICBt X3BhcmVudFdpbmRvdyA9IFhDcmVhdGVXaW5kb3cobV9kaXNwbGF5LAogICAgICAgICBSb290V2lu ZG93T2ZTY3JlZW4oc2NyZWVuKSwKLSAgICAgICAgV2lkdGhPZlNjcmVlbihzY3JlZW4pICsgMSwg MCwgMSwgMSwKKyAgICAgICAgLTEsIC0xLCAxLCAxLAogICAgICAgICAwLAogICAgICAgICBnZGtf dmlzdWFsX2dldF9kZXB0aCh2aXN1YWwpLAogICAgICAgICBJbnB1dE91dHB1dCwK