145817 2015-06-09 14:33:27 -0700 GraphicsContext state stack wasting lots of memory when empty. 2015-06-09 17:47:26 -0700 1 1 1 Unclassified WebKit Canvas 528+ (Nightly build) Unspecified Unspecified RESOLVED FIXED Performance P2 Normal --- 1 kling kling commit-queue ggaren kling oldest_to_newest 1100800 0 kling 2015-06-09 14:33:27 -0700 GraphicsContext::restore() uses removeLast() which never nukes the Vector<State>'s backing store. This means that we always have capacity for at least 16 states in each GraphicsContext that has ever save()d. Since canvas elements have a persistent GraphicsContext, this adds up to a bunch of memory with multiple canvases around. 1100804 1 254604 kling 2015-06-09 14:53:33 -0700 Created attachment 254604 Patch 1100812 2 254604 ggaren 2015-06-09 15:14:17 -0700 Comment on attachment 254604 Patch View in context: https://bugs.webkit.org/attachment.cgi?id=254604&action=review r=me > Source/WebCore/platform/graphics/GraphicsContext.cpp:140 > + // Make sure we deallocate the state stack buffer when it goes empty. > + // Canvas elements will immediately save() again, but that goes into inline capacity. > + if (m_stack.isEmpty()) > + m_stack.clear(); Should Vector do this automatically? 1100813 3 ggaren 2015-06-09 15:14:47 -0700 To elaborate, I really hate it that std::vector does not do this automatically. At the limit, you have to add a call to clear to every client! 1100843 4 kling 2015-06-09 16:19:05 -0700 (In reply to comment #3) > To elaborate, I really hate it that std::vector does not do this > automatically. At the limit, you have to add a call to clear to every client! I guess you mean WTF::Vector. We can totes do that. Let's separate the issues though. 1100853 5 ggaren 2015-06-09 16:32:41 -0700 > > To elaborate, I really hate it that std::vector does not do this > > automatically. At the limit, you have to add a call to clear to every client! > > I guess you mean WTF::Vector. > We can totes do that. Let's separate the issues though. No, I mean that std::vector never ever shrinks until you call shrink_to_fit, which is super annoying, while WTF::Vector often shrinks automatically, but misses in this case. 1100874 6 254604 commit-queue 2015-06-09 17:47:23 -0700 Comment on attachment 254604 Patch Clearing flags on attachment: 254604 Committed r185396: <http://trac.webkit.org/changeset/185396> 1100875 7 commit-queue 2015-06-09 17:47:26 -0700 All reviewed patches have been landed. Closing bug. 254604 2015-06-09 14:53:33 -0700 2015-06-09 17:47:23 -0700 Patch bug-145817.diff text/plain 2243 kling ZGlmZiAtLWdpdCBhL1NvdXJjZS9XZWJDb3JlL0NoYW5nZUxvZyBiL1NvdXJjZS9XZWJDb3JlL0No YW5nZUxvZwppbmRleCA2OWYxZDU4Li42MTM4ZGEzIDEwMDY0NAotLS0gYS9Tb3VyY2UvV2ViQ29y ZS9DaGFuZ2VMb2cKKysrIGIvU291cmNlL1dlYkNvcmUvQ2hhbmdlTG9nCkBAIC0xLDMgKzEsMjMg QEAKKzIwMTUtMDYtMDkgIEFuZHJlYXMgS2xpbmcgIDxha2xpbmdAYXBwbGUuY29tPgorCisgICAg ICAgIEdyYXBoaWNzQ29udGV4dCBzdGF0ZSBzdGFjayB3YXN0aW5nIGxvdHMgb2YgbWVtb3J5IHdo ZW4gZW1wdHkuCisgICAgICAgIDxodHRwczovL3dlYmtpdC5vcmcvYi8xNDU4MTc+CisKKyAgICAg ICAgUmV2aWV3ZWQgYnkgTk9CT0RZIChPT1BTISkuCisKKyAgICAgICAgR2l2ZSB0aGUgR3JhcGhp Y3NDb250ZXh0U3RhdGUgc3RhY2sgYW4gaW5saW5lIGNhcGFjaXR5IG9mIDEsIGFuZCBtYWtlIHN1 cmUKKyAgICAgICAgdG8gZnJlZSBhbnkgaGVhcC1hbGxvY2F0ZWQgYmFja2luZyBzdG9yZSB3aGVu IHRoZSBzdGFjayBnb2VzIGVtcHR5LgorCisgICAgICAgIFRoZSAxIGlzIGJlY2F1c2UgSFRNTENh bnZhc0VsZW1lbnQga2VlcHMgb25lICJzYXZlIiBvbiB0aGUgdW5kZXJseWluZworICAgICAgICBH cmFwaGljc0NvbnRleHQgYXQgYWxsIHRpbWVzLCBhbmQgdGhpcyBwcmV2ZW50cyB0aG9zZSBjYW52 YXNlcyBmcm9tIGFsd2F5cworICAgICAgICBzaXR0aW5nIG9uIGFuIGVtcHR5IHN0YWNrIHdpdGgg MTYgY2FwYWNpdHkuCisKKyAgICAgICAgVGhpcyBzYXZlcyB+NTIwIGtCIG9uIGNuZXQuY29tIHZp ZGVvIHBhZ2VzLgorCisgICAgICAgICogcGxhdGZvcm0vZ3JhcGhpY3MvR3JhcGhpY3NDb250ZXh0 LmNwcDoKKyAgICAgICAgKFdlYkNvcmU6OkdyYXBoaWNzQ29udGV4dDo6cmVzdG9yZSk6CisgICAg ICAgICogcGxhdGZvcm0vZ3JhcGhpY3MvR3JhcGhpY3NDb250ZXh0Lmg6CisKIDIwMTUtMDYtMDkg IERhcmluIEFkbGVyICA8ZGFyaW5AYXBwbGUuY29tPgogCiAgICAgICAgIEZvbGxvdy11cCBmaXgg Zm9yOgpkaWZmIC0tZ2l0IGEvU291cmNlL1dlYkNvcmUvcGxhdGZvcm0vZ3JhcGhpY3MvR3JhcGhp Y3NDb250ZXh0LmNwcCBiL1NvdXJjZS9XZWJDb3JlL3BsYXRmb3JtL2dyYXBoaWNzL0dyYXBoaWNz Q29udGV4dC5jcHAKaW5kZXggMTMzNzg3ODAuLmQzOGMxZmEgMTAwNjQ0Ci0tLSBhL1NvdXJjZS9X ZWJDb3JlL3BsYXRmb3JtL2dyYXBoaWNzL0dyYXBoaWNzQ29udGV4dC5jcHAKKysrIGIvU291cmNl L1dlYkNvcmUvcGxhdGZvcm0vZ3JhcGhpY3MvR3JhcGhpY3NDb250ZXh0LmNwcApAQCAtMTM0LDYg KzEzNCwxMSBAQCB2b2lkIEdyYXBoaWNzQ29udGV4dDo6cmVzdG9yZSgpCiAgICAgbV9zdGF0ZSA9 IG1fc3RhY2subGFzdCgpOwogICAgIG1fc3RhY2sucmVtb3ZlTGFzdCgpOwogCisgICAgLy8gTWFr ZSBzdXJlIHdlIGRlYWxsb2NhdGUgdGhlIHN0YXRlIHN0YWNrIGJ1ZmZlciB3aGVuIGl0IGdvZXMg ZW1wdHkuCisgICAgLy8gQ2FudmFzIGVsZW1lbnRzIHdpbGwgaW1tZWRpYXRlbHkgc2F2ZSgpIGFn YWluLCBidXQgdGhhdCBnb2VzIGludG8gaW5saW5lIGNhcGFjaXR5LgorICAgIGlmIChtX3N0YWNr LmlzRW1wdHkoKSkKKyAgICAgICAgbV9zdGFjay5jbGVhcigpOworCiAgICAgcmVzdG9yZVBsYXRm b3JtU3RhdGUoKTsKIH0KIApkaWZmIC0tZ2l0IGEvU291cmNlL1dlYkNvcmUvcGxhdGZvcm0vZ3Jh cGhpY3MvR3JhcGhpY3NDb250ZXh0LmggYi9Tb3VyY2UvV2ViQ29yZS9wbGF0Zm9ybS9ncmFwaGlj cy9HcmFwaGljc0NvbnRleHQuaAppbmRleCAwNTI0NmNhLi4zNjViY2IwIDEwMDY0NAotLS0gYS9T b3VyY2UvV2ViQ29yZS9wbGF0Zm9ybS9ncmFwaGljcy9HcmFwaGljc0NvbnRleHQuaAorKysgYi9T b3VyY2UvV2ViQ29yZS9wbGF0Zm9ybS9ncmFwaGljcy9HcmFwaGljc0NvbnRleHQuaApAQCAtNTU5 LDcgKzU1OSw3IEBAIG5hbWVzcGFjZSBXZWJDb3JlIHsKICAgICAgICAgR3JhcGhpY3NDb250ZXh0 UGxhdGZvcm1Qcml2YXRlKiBtX2RhdGE7CiAKICAgICAgICAgR3JhcGhpY3NDb250ZXh0U3RhdGUg bV9zdGF0ZTsKLSAgICAgICAgVmVjdG9yPEdyYXBoaWNzQ29udGV4dFN0YXRlPiBtX3N0YWNrOwor ICAgICAgICBWZWN0b3I8R3JhcGhpY3NDb250ZXh0U3RhdGUsIDE+IG1fc3RhY2s7CiAgICAgICAg IGJvb2wgbV91cGRhdGluZ0NvbnRyb2xUaW50czsKICAgICAgICAgdW5zaWduZWQgbV90cmFuc3Bh cmVuY3lDb3VudDsKICAgICB9Owo=