)]}' { "commit": "d832bdc7902d607573ca3e476263b423c96b6997", "tree": "400d0f98c0f46b7053cb01cfc060596b46ff76c8", "parents": [ "6f2e304938da568b473d43dbe09c8abc147c7541" ], "author": { "name": "Findit", "email": "findit-for-me@appspot.gserviceaccount.com", "time": "Fri Apr 23 05:05:28 2021" }, "committer": { "name": "Copybara-Service", "email": "copybara-worker@google.com", "time": "Fri Apr 23 05:22:57 2021" }, "message": "Revert \"Add SubframeShutdownDelay experiment\"\n\nThis reverts commit 3447a7a52eecea83be3ddb03ae65d4c2f8df5b43.\n\nReason for revert:\n\nNote: It is reported that sheriffs cannot submit CL created by Findit\n(crbug.com/1187426). A workaround in the mean time is to abandon this\nCL and create another revert CL.\n\nFindit (https://goo.gl/kROfz5) identified CL at revision 875466 as the\nculprit for failures in the build cycles as shown on:\nhttps://analysis.chromium.org/waterfall/culprit?key\u003dag9zfmZpbmRpdC1mb3ItbWVyRAsSDVdmU3VzcGVjdGVkQ0wiMWNocm9taXVtLzM0NDdhN2E1MmVlY2VhODNiZTNkZGIwM2FlNjVkNGMyZjhkZjViNDMM\n\nSample Failed Build: https://ci.chromium.org/b/8849198831280035280\n\nSample Failed Step: content_unittests\n\nOriginal change\u0027s description:\n\u003e Add SubframeShutdownDelay experiment\n\u003e\n\u003e This change adds experiment SubframeShutdownDelay, which delays\n\u003e shutdown of subframe renderer processes by a few seconds. This\n\u003e experiment aims to increase the chance for subframe processes to be\n\u003e reused, particularly when navigating between pages that share a common\n\u003e subframe domain. Successful subframe-process reuse saves the cost of\n\u003e process recreation, which can take ~3 seconds of CPU time per\n\u003e navigation. This savings needs to be balanced against the memory cost\n\u003e of keeping each subframe renderer alive a few seconds longer.\n\u003e\n\u003e To this end, the experiment has multiple branches with different\n\u003e delays, in order to determine the best-performing method:\n\u003e * constant: a flat 2s delay\n\u003e * constant-long: a flat 8s delay\n\u003e * history-based: a 0-8s delay; the median\n\u003e TimeSinceReusableProcessDestroyed in the past 5 subframe\n\u003e navigations, with \"no reuse possible\" counting as 0s\n\u003e * history-based-long: a 0-8s delay; the 75th-percentile\n\u003e TimeSinceReusableProcessDestroyed in the past 5 subframe\n\u003e navigations, with \"no reuse possible\" counting as 0s\n\u003e * memory-based: a 2s delay when available memory is under 8 GB, and a\n\u003e 2-8s delay when it is higher, up to 16 GB\n\u003e\n\u003e These will be enabled via Finch, and can be manually enabled by\n\u003e appending command-line flag:\n\u003e --enable-features\u003d\"SubframeShutdownDelay:type/constant\n\u003e where \"constant\" can be any of the above experiment labels.\n\u003e\n\u003e Design doc:\n\u003e https://docs.google.com/document/d/1x_h4Gg4ForILEj8A4rMBX6d84uHWyQ9RSXmGVqMlBTk/edit\n\u003e\n\u003e Bug: 894253\n\u003e Change-Id: I64c64532d6185412d7f3f97bf9917de9574aecc4\n\u003e Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2431587\n\u003e Commit-Queue: Jesse McKenna \u003cjessemckenna@google.com\u003e\n\u003e Reviewed-by: Alex Moshchuk \u003calexmos@chromium.org\u003e\n\u003e Reviewed-by: Olivier Li \u003colivierli@chromium.org\u003e\n\u003e Cr-Commit-Position: refs/heads/master@{#875466}\n\nChange-Id: Ieab89a6fe5aba60abdf08f0b9b86e8e160c694e1\nNo-Presubmit: true\nNo-Tree-Checks: true\nNo-Try: true\nBug: 894253\nReviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2847642\nReviewed-by: My Nguyen \u003cmyy@chromium.org\u003e\nCommit-Queue: My Nguyen \u003cmyy@chromium.org\u003e\nOwners-Override: My Nguyen \u003cmyy@chromium.org\u003e\nCr-Commit-Position: refs/heads/master@{#875526}\nGitOrigin-RevId: 6a9440ddbb65844905eb7f442623b2431df20d07\n", "tree_diff": [ { "type": "modify", "old_id": "2a7024ffb2e5fee4ff4a4418042a33f94776ab3f", "old_mode": 33188, "old_path": "metrics/histograms/enums.xml", "new_id": "360b8299b239dfcfc3630b9392727da4facdb426", "new_mode": 33188, "new_path": "metrics/histograms/enums.xml" } ] }