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  1. 08 Feb, 2022 1 commit
    • Benedikt Meurer's avatar
      [debug] Implement stepping out of async functions in the debugger. · 536e96cc
      Benedikt Meurer authored 
      Previously the inspector was trying to handle step-out for async
functions by annotating the async stacks, but this was merely a
hack and didn't work reliably

(a) when the async caller that is `await`ing the result of the
    callee was still in the synchronous part (because then there
    was no async task yet in the inspector), or
(b) not at all when the async stack tracking wasn't enabled or the
    maximum async stack depth was too small.

This CL replaces that hack with a pragmatic solution inside the
V8 debugger, where upon `await` we memorize the async function
object of the caller on the outer promise of the callee, and when
stepping out of the callee we check whether the returned promise
has a memorized async function object and if so, we schedule that
to resume.

This CL thereby effectively reverts https://crrev.com/c/1054618
and replaces it with a V8 debug solution, and thereby further
reduces the (memory) overhead of an AsyncStackTrace.

Fixed: chromium:1246867
Bug: v8:6161, v8:7753, chromium:1277451, chromium:1280519
Change-Id: I6aa79e90f49d204f66bfd37e7a328c7fb8d635b1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3439865Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Auto-Submit: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78990}
      536e96cc
  3. 04 Feb, 2022 1 commit
  5. 04 Jan, 2022 2 commits
  7. 03 Jan, 2022 1 commit
    • Benedikt Meurer's avatar
      Revert "[inspector] Fix `Runtime.setMaxCallStackSizeToCapture`." · c51b582d
      Benedikt Meurer authored 
      This reverts commit 34f73cc7.

Reason for revert: Performance regressions throughout a lot of
system health and browsing benchmarks.

Original change's description:
> [inspector] Fix `Runtime.setMaxCallStackSizeToCapture`.
>
> This change fixes the implementation of the previously introduced API
> `Runtime.setMaxCallStackSizeToCapture` to work correctly and also apply
> (consistently) to stack traces captured by V8 when exceptions are
> thrown. It does so in a fully backwards compatible manner.
>
> This change thus makes the previous fix for catapult (which landed in
> http://crrev.com/c/3347789) effective, and therefore ensures that real
> world performance benchmarks aren't affected by the use of the `Runtime`
> domain in the catapult test framework.
>
> Bug: chromium:1283162, chromium:1278650, chromium:1258599
> Bug: chromium:1280803, chromium:1280832, chromium:1280818
> Fixed: chromium:1280831
> Doc: https://bit.ly/v8-cheaper-inspector-stack-traces
> Change-Id: I4ec951a858317fa49096cd4023deb0104d92c9c9
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3361839
> Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
> Auto-Submit: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#78458}

Bug: chromium:1283162, chromium:1278650, chromium:1258599
Bug: chromium:1280803, chromium:1280832, chromium:1280818
Bug: chromium:1280831
Change-Id: Id1efaffa2f7f08c47f833f68b8a297494edee21e
Fixed: chromium:1283751, chromium:1283749, chromium:1283746
Fixed: chromium:1283729, chromium:1283700, chromium:1283700
Fixed: chromium:1283691, chromium:1283687, chromium:1283678
Fixed: chromium:1283677, chromium:1283676, chromium:1283675
Fixed: chromium:1283674, chromium:1283618, chromium:1283536
Fixed: chromium:1283523, chromium:1283516
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3364078
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Auto-Submit: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78462}
      c51b582d
  9. 31 Dec, 2021 1 commit
  11. 24 Nov, 2021 1 commit
  13. 11 Nov, 2021 1 commit
    • Benedikt Meurer's avatar
      [inspector] Cache StackFrames by script, line and column number. · e60dc99e
      Benedikt Meurer authored 
      This introduces a stack frame cache on the V8Debugger level, which
de-duplicates StackFrame instances based on their scriptId, line and
column number.

This greatly reduces the memory pressure when debugging huge Web
applications that have a lot of async activity (and potentially
have scripts with huge URLs). This is guided by the observation
that even in huge applications, there are only a very limited
number of call sites that initiate async activity and hence we
only have a limited number of distinct StackFrames to worry
about (despite having to maintain a large number of async stack
traces overall).

As a nice side effect, this CL also greatly reduces the negative
performance impact of collecting async stack traces in these
huge applications.

Generally speaking this is mostly duct tape however, and we might
want to follow up with changes to make capturing (and storing)
stack frames even cheaper.

Fixed: chromium:1268436
Change-Id: Ib212b3c97dce2bb7ca47d5875d45cf20b9b97afe
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3272577
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarSimon Zünd <szuend@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77835}
      e60dc99e
  15. 30 Sep, 2021 1 commit
    • Benedikt Meurer's avatar
      [inspector] Align async task frame reporting for `await`. · d6c01059
      Benedikt Meurer authored 
      The V8 Inspector was sending an additional frame as part of async stack
traces for async functions, which pointed to the first executed `await`
in the async function. This is leaking an implementation detail of how
(and more precisely when) the inspector decides to collect this stack
trace. From the users perspective the async part of the stack trace is
supposed to capture what happened _prior to the task_ - meaning in case
of async functions: What lead to the execution of the async function.
This is reflected by the fact that the DevTools front-end (and the V8
Inspector itself) performs post-processing on these async call stacks,
removing the misleading top frame from it. But this post-processing is
not applied consistently to all async stack traces (i.e. the Console
message stack traces don't get this), and potentially also not applied
consistently across consumers of the Chromium debugger backend.

Instead the V8 Inspector now removes the top frame itself and thus
reports `await` consistently with how other async tasks are reported to
debugger front-ends.

Note: This preserves backwards compatibility with old versions of
devtools-frontend, which do post-processing (for the Call Stack) only on
async stack traces marked with "async function", while we now mark these
async stack traces with "await" instead (aligned with what the front-end
is using as user visibile string anyways in the Call Stack section, and
this matching will be updated in a separate follow up CL to look for
"await" instead of "async function").

Before: https://imgur.com/kIrWcIc.png
After: https://imgur.com/HvZGqiP
Fixed: chromium:1254259
Bug: chromium:1229662
Change-Id: I57ce051a28892177b6b96221f083ae957f967e52
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3193535
Auto-Submit: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarKim-Anh Tran <kimanh@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77157}
      d6c01059
  17. 23 Jul, 2021 1 commit
  19. 25 Jun, 2021 1 commit
  21. 10 May, 2021 1 commit
  23. 06 May, 2021 1 commit
    • Benedikt Meurer's avatar
      [inspector] Consistently pass around script ID as integer. · 51fe5571
      Benedikt Meurer authored 
      Within the inspector we should be consistent about passing the script ID
always as integer, and only convert to String16 when actually needed.
That (a) saves memory (and some runtime overhead) when stashing away
call frames, for example in case of async stack traces, and (b) reduces
confusion which representation to chose.

Bug: chromium:1162229
Change-Id: I9591931da0a307779372f36aba6e155ec22bbe3d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2876856
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Auto-Submit: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74410}
      51fe5571
  25. 13 Jan, 2021 1 commit
  27. 15 Dec, 2020 1 commit
  29. 22 Oct, 2020 1 commit
  31. 17 Aug, 2020 1 commit
  33. 25 Mar, 2020 1 commit
  35. 09 Feb, 2020 1 commit
  37. 04 Feb, 2020 1 commit
  39. 24 Jan, 2020 1 commit
  41. 22 Jan, 2020 1 commit
  43. 09 Jan, 2020 1 commit
  45. 20 Sep, 2019 1 commit
  47. 12 Sep, 2019 1 commit
  49. 10 Sep, 2019 1 commit
  51. 26 Jun, 2019 1 commit
  53. 15 Jun, 2019 1 commit
  55. 18 Oct, 2018 1 commit
  57. 18 Sep, 2018 2 commits
  59. 09 Aug, 2018 1 commit
    • Alexey Kozyatinskiy's avatar
      [inspector] added V8InspectorClient::resourceNameToUrl · dbfcc487
      Alexey Kozyatinskiy authored 
      Some clients (see Node.js) use platform path as ScriptOrigin.
Reporting platform path in protocol makes using protocol much harder.
This CL introduced V8InspectorClient::resourceNameToUrl method that
is called for any reported using protocol url.
V8Inspector uses url internally as well so protocol client may generate
pattern for blackboxing with file urls only and does not need to build
complicated regexp that covers files urls and platform paths on
different platforms.

R=lushnikov@chromium.org
TBR=yangguo@chromium.org

Bug: none
Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel;luci.chromium.try:linux_chromium_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: Iff302e7441df922fa5d689fe510f5a9bfd470b9b
Reviewed-on: https://chromium-review.googlesource.com/1164624
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: 's avatarAlexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55029}
      dbfcc487
  61. 25 Jul, 2018 1 commit
  63. 23 Jul, 2018 1 commit
  65. 04 Jun, 2018 1 commit
  67. 31 May, 2018 1 commit
  69. 30 May, 2018 1 commit
  71. 07 May, 2018 1 commit
  73. 14 Dec, 2017 1 commit
  75. 23 Nov, 2017 1 commit