The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4511cbf532f768d5eb320850cd908f26fc4d93f1

commit 4511cbf532f768d5eb320850cd908f26fc4d93f1
Author: Dmitry Skiba <dskiba@chromium.org>
Date: Thu Dec 07 01:33:28 2017

Make memory ablation payload incompressible.

Memory ablation payload is just a single dirty byte in otherwise zero
page. The lz4 compression ratio of such page is 151, i.e. the effect
of the payload greatly reduces as its pages are moved into zram.

This CL fills the payload with random bytes to make sure its effect
is not diminished by zram.

Measurements on 1GiB Android Go device show that this change increases
time spent on touching one chunk (512KiB) by 30% (2.7ms to 3.5ms).

Bug: 710048
Change-Id: I1e5cfebb1593bf3c3a917fd40fd689e43a144263
Reviewed-on: https://chromium-review.googlesource.com/809962
Reviewed-by: Erik Chen <erikchen@chromium.org>
Reviewed-by: Maria Khomenko <mariakhomenko@chromium.org>
Reviewed-by: Brett Wilson <brettw@chromium.org>
Commit-Queue: Dmitry Skiba <dskiba@chromium.org>
Cr-Commit-Position: refs/heads/master@{#522294}
[modify] https://crrev.com/4511cbf532f768d5eb320850cd908f26fc4d93f1/chrome/browser/experiments/memory_ablation_experiment.cc

Requesting merge for the CL above that changes how memory ablation payloads are compressed. This will allow us to run the experiment more correctly under memory pressure.

This bug requires manual review: M64 has already been promoted to the beta branch, so this requires manual review
Please contact the milestone owner if you have questions.
Owners: cmasso@(Android), cmasso@(iOS), kbleicher@(ChromeOS), abdulsyed@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Please verify in Canary and confirm it looks good.

Ran an ablation experiment in canary for a week. Verified no new crashes in crash/ and metrics look consistent with what we expect. Please approve merge.

The following revision refers to this bug:
https://chromium.googlesource.com/chromium/src.git/+/13ba4c13a018bb6ad7ba551167ff24acba7730ed

commit 13ba4c13a018bb6ad7ba551167ff24acba7730ed
Author: Dmitry Skiba <dskiba@chromium.org>
Date: Sat Dec 23 16:24:44 2017


Make memory ablation payload incompressible.

Memory ablation payload is just a single dirty byte in otherwise zero
page. The lz4 compression ratio of such page is 151, i.e. the effect
of the payload greatly reduces as its pages are moved into zram.

This CL fills the payload with random bytes to make sure its effect
is not diminished by zram.

Measurements on 1GiB Android Go device show that this change increases
time spent on touching one chunk (512KiB) by 30% (2.7ms to 3.5ms).

Bug: 710048
Change-Id: I1e5cfebb1593bf3c3a917fd40fd689e43a144263
Reviewed-on: https://chromium-review.googlesource.com/809962
Reviewed-by: Erik Chen <erikchen@chromium.org>
Reviewed-by: Maria Khomenko <mariakhomenko@chromium.org>
Reviewed-by: Brett Wilson <brettw@chromium.org>
Commit-Queue: Dmitry Skiba <dskiba@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#522294}(cherry picked from commit 4511cbf532f768d5eb320850cd908f26fc4d93f1)
Reviewed-on: https://chromium-review.googlesource.com/843602
Cr-Commit-Position: refs/branch-heads/3282@{#352}
Cr-Branched-From: 5fdc0fab22ce7efd32532ee989b223fa12f8171e-refs/heads/master@{#520840}
[modify] https://crrev.com/13ba4c13a018bb6ad7ba551167ff24acba7730ed/chrome/browser/experiments/memory_ablation_experiment.cc
…