165242 2016-11-30 22:01:41 -0800 REGRESSION (209168!): IndexedDB.IndexedDBMultiProcess and IndexedDB.WebProcessKillIDBCleanup are timing out 2016-11-30 23:06:38 -0800 1 1 1 Unclassified WebKit WebCore Misc. WebKit Nightly Build Unspecified Unspecified RESOLVED FIXED P2 Normal --- 160306 1 beidson webkit-unassigned ryanhaddad oldest_to_newest 1255151 0 beidson 2016-11-30 22:01:41 -0800 REGRESSION: IndexedDB.IndexedDBMultiProcess and IndexedDB.WebProcessKillIDBCleanup are timing out Seems they're timing out reliably in most (if not all) configs. 1255152 1 beidson 2016-11-30 22:04:05 -0800 Trying to track down when this started (probably one of my checkins today) 1255153 2 beidson 2016-11-30 22:05:49 -0800 I can reproduce locally (95% of the time) 1255161 3 beidson 2016-11-30 22:55:04 -0800 Focusing on IndexedDB.IndexedDBMultiProcess locally. I'm not sure this was related to my changes from today. The test loads 3 html files serially. Each HTML file is expected to communicate back to the native code via various messages. The first test is supposed to message back: 1 - That an upgrade transaction started (via the javascript onupgradeneeded event handler) 2 - That the transaction completed (via the javascript oncomplete event handler) 3 - That the open request succeeded (via the javascript onsuccess event handler) I've verified through code, in no uncertain terms, that each of those 3 events are firing in the correct order. But when the test hangs, only message #1 and #3 makes it back to native code. Message #2 is lost somehow. I've confirmed that event #2 *is firing* and *is being handled*, because I've given it side effects that are observed in message #3... yet message #2 never makes it. 1255162 4 beidson 2016-11-30 22:55:21 -0800 Additionally, this only happens "sometimes", even if it's most of the time. 1255163 5 beidson 2016-11-30 22:57:46 -0800 The event handler in question is as follows: event.target.transaction.oncomplete = function() { window.webkit.messageHandlers.testHandler.postMessage('Transaction complete'); } ~95% of the time, that message never gets back to native code. Sometimes it does. If I change it to the following: sawTransactionComplete = false; event.target.transaction.oncomplete = function() { window.webkit.messageHandlers.testHandler.postMessage('Transaction complete'); sawTransactionComplete = true; } ... and then pass the value of sawTransactionComplete through to the onsuccess event handler message, native code sees that sawTransactionComplete is in fact true. If I change it to the following: event.target.transaction.oncomplete = function() { window.webkit.messageHandlers.testHandler.postMessage('Transaction complete'); alert("Made it here!"); } Then the existence of that alert() call makes the test reliably pass! 1255164 6 beidson 2016-11-30 23:01:34 -0800 Based on the history of this one bot: https://build.webkit.org/buildslaves/bot165 Revision 209167 worked but revision 209169 failed. https://trac.webkit.org/changeset/209168 is of course a (surprising) candidate. Other bots seem to confirm. 1255169 7 beidson 2016-11-30 23:06:38 -0800 Rolled out in https://trac.webkit.org/changeset/209176