Use TaskScheduler instead of WorkerPool in navigation_entry_screenshot_manager.cc.

Use TaskScheduler instead of WorkerPool in navigation_entry_screenshot_manager.cc.

The following traits are used:

Priority: Inherited (default)
  The priority is inherited from the calling context (i.e. TaskTraits
  are initialized with the priority of the current task).

Shutdown behavior: CONTINUE_ON_SHUTDOWN
  Tasks posted with this mode which have not started executing before
  shutdown is initiated will never run. Tasks with this mode running at
  shutdown will be ignored (the worker will not be joined).

  Note: Tasks that were previously posted to base::WorkerPool should
  use this shutdown behavior because this is how base::WorkerPool
  handles all its tasks.

Does Not Block (default):
  Tasks without the MayBlock() and WithBaseSyncPrimitives() traits
  may not block.

BUG=659191
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation

Committed: https://crrev.com/9b818f0b639e940db0167e82e0bc071852d30dc0
Cr-Commit-Position: refs/heads/master@{#441316}

[fdoray, 2016-12-31 21:10:34]

Description was changed from

==========
Use TaskScheduler instead of WorkerPool in
navigation_entry_screenshot_manager.cc.

The following traits are used:

Priority: Inherited (default)
  The priority is inherited from the calling context (i.e. TaskTraits
  are initialized with the priority of the current task).

Shutdown behavior: CONTINUE_ON_SHUTDOWN
  Tasks posted with this mode which have not started executing before
  shutdown is initiated will never run. Tasks with this mode running at
  shutdown will be ignored (the worker will not be joined).

  Note: Tasks that were previously posted to base::WorkerPool should
  use this shutdown behavior because this is how base::WorkerPool
  handles all its tasks.

Does Not Block (default):
  Tasks without the MayBlock() and WithBaseSyncPrimitives() traits
  may not block.

BUG=659191
==========

to

==========
Use TaskScheduler instead of WorkerPool in
navigation_entry_screenshot_manager.cc.

The following traits are used:

Priority: Inherited (default)
  The priority is inherited from the calling context (i.e. TaskTraits
  are initialized with the priority of the current task).

Shutdown behavior: CONTINUE_ON_SHUTDOWN
  Tasks posted with this mode which have not started executing before
  shutdown is initiated will never run. Tasks with this mode running at
  shutdown will be ignored (the worker will not be joined).

  Note: Tasks that were previously posted to base::WorkerPool should
  use this shutdown behavior because this is how base::WorkerPool
  handles all its tasks.

Does Not Block (default):
  Tasks without the MayBlock() and WithBaseSyncPrimitives() traits
  may not block.

BUG=659191
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation
==========

[fdoray, 2016-12-31 21:10:36]

The CQ bit was checked by fdoray@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-12-31 21:10:44]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-12-31 22:20:41]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-12-31 22:20:42]

Dry run: This issue passed the CQ dry run.

[fdoray, 2017-01-01 19:23:15]

fdoray@chromium.org changed reviewers:
+ alexmos@chromium.org

[fdoray, 2017-01-01 19:23:16]

PTAL. WorkerPool is being deprecated in favor of TaskScheduler.

[alexmos, 2017-01-03 19:19:06]

https://codereview.chromium.org/2604343002/diff/1/content/browser/frame_host/...
File content/browser/frame_host/navigation_entry_screenshot_manager.cc (left):

https://codereview.chromium.org/2604343002/diff/1/content/browser/frame_host/...
content/browser/frame_host/navigation_entry_screenshot_manager.cc:40: true)) {
Is there's an equivalent to task_is_slow in TaskScheduler?  I'm not too familiar
with how important this is -- is it ok to lose it?

[fdoray, 2017-01-04 00:27:09]

PTAnL

https://codereview.chromium.org/2604343002/diff/1/content/browser/frame_host/...
File content/browser/frame_host/navigation_entry_screenshot_manager.cc (left):

https://codereview.chromium.org/2604343002/diff/1/content/browser/frame_host/...
content/browser/frame_host/navigation_entry_screenshot_manager.cc:40: true)) {
On 2017/01/03 19:19:06, alexmos wrote:
> Is there's an equivalent to task_is_slow in TaskScheduler?  I'm not too
familiar
> with how important this is -- is it ok to lose it?

|task_is_slow| is ignored by WorkerPool and developers told us that they don't
like the fact that there are no clear guidelines to determine whether a task is
slow.

There is no equivalent to |task_is_slow| in TaskScheduler. However, there is a
MayBlock() trait for tasks that block (e.g. synchronously read a file from
disk).  When a MayBlock() task takes a long time to run, TaskScheduler may
decide to create a new thread (note that TaskScheduler dynamically determines
whether a task takes a long time to run).

FWICT, ScreenshotData::EncodeOnWorker is CPU-bound. Therefore, it should not be
posted with MayBlock().

[alexmos, 2017-01-04 01:00:08]

LGTM

https://codereview.chromium.org/2604343002/diff/1/content/browser/frame_host/...
File content/browser/frame_host/navigation_entry_screenshot_manager.cc (left):

https://codereview.chromium.org/2604343002/diff/1/content/browser/frame_host/...
content/browser/frame_host/navigation_entry_screenshot_manager.cc:40: true)) {
On 2017/01/04 00:27:09, fdoray wrote:
> On 2017/01/03 19:19:06, alexmos wrote:
> > Is there's an equivalent to task_is_slow in TaskScheduler?  I'm not too
> familiar
> > with how important this is -- is it ok to lose it?
> 
> |task_is_slow| is ignored by WorkerPool

At least on Windows, it seems to be used to add WT_EXECUTELONGFUNCTION to
QueueUserWorkItem flags, see 
https://cs.chromium.org/chromium/src/base/threading/worker_pool_win.cc?l=46

Losing that was mostly why I was curious about this.

> and developers told us that they don't
> like the fact that there are no clear guidelines to determine whether a task
is
> slow.
> 
> There is no equivalent to |task_is_slow| in TaskScheduler. However, there is a
> MayBlock() trait for tasks that block (e.g. synchronously read a file from
> disk).  When a MayBlock() task takes a long time to run, TaskScheduler may
> decide to create a new thread (note that TaskScheduler dynamically determines
> whether a task takes a long time to run).
> 
> FWICT, ScreenshotData::EncodeOnWorker is CPU-bound. Therefore, it should not
be
> posted with MayBlock().

Acknowledged.

[fdoray, 2017-01-04 02:13:15]

https://codereview.chromium.org/2604343002/diff/1/content/browser/frame_host/...
File content/browser/frame_host/navigation_entry_screenshot_manager.cc (left):

https://codereview.chromium.org/2604343002/diff/1/content/browser/frame_host/...
content/browser/frame_host/navigation_entry_screenshot_manager.cc:40: true)) {
On 2017/01/04 01:00:08, alexmos wrote:
> On 2017/01/04 00:27:09, fdoray wrote:
> > On 2017/01/03 19:19:06, alexmos wrote:
> > > Is there's an equivalent to task_is_slow in TaskScheduler?  I'm not too
> > familiar
> > > with how important this is -- is it ok to lose it?
> > 
> > |task_is_slow| is ignored by WorkerPool
> 
> At least on Windows, it seems to be used to add WT_EXECUTELONGFUNCTION to
> QueueUserWorkItem flags, see 
> https://cs.chromium.org/chromium/src/base/threading/worker_pool_win.cc?l=46
> 
> Losing that was mostly why I was curious about this.
> 
> > and developers told us that they don't
> > like the fact that there are no clear guidelines to determine whether a task
> is
> > slow.
> > 
> > There is no equivalent to |task_is_slow| in TaskScheduler. However, there is
a
> > MayBlock() trait for tasks that block (e.g. synchronously read a file from
> > disk).  When a MayBlock() task takes a long time to run, TaskScheduler may
> > decide to create a new thread (note that TaskScheduler dynamically
determines
> > whether a task takes a long time to run).
> > 
> > FWICT, ScreenshotData::EncodeOnWorker is CPU-bound. Therefore, it should not
> be
> > posted with MayBlock().
> 
> Acknowledged.

Our experiments show that this flag is ignored on newer versions of Windows (it
was used on XP).

[fdoray, 2017-01-04 02:13:20]

The CQ bit was checked by fdoray@chromium.org

[commit-bot: I haz the power, 2017-01-04 02:13:48]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-01-04 04:27:18]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1483496000519880, "parent_rev":
"89317cd02aea67a6ce10de1ad55156a89984d8dd", "commit_rev":
"7d8f0452363b5ec1af06dfc3b076801267632f85"}

[commit-bot: I haz the power, 2017-01-04 04:28:18]

Description was changed from

==========
Use TaskScheduler instead of WorkerPool in
navigation_entry_screenshot_manager.cc.

The following traits are used:

Priority: Inherited (default)
  The priority is inherited from the calling context (i.e. TaskTraits
  are initialized with the priority of the current task).

Shutdown behavior: CONTINUE_ON_SHUTDOWN
  Tasks posted with this mode which have not started executing before
  shutdown is initiated will never run. Tasks with this mode running at
  shutdown will be ignored (the worker will not be joined).

  Note: Tasks that were previously posted to base::WorkerPool should
  use this shutdown behavior because this is how base::WorkerPool
  handles all its tasks.

Does Not Block (default):
  Tasks without the MayBlock() and WithBaseSyncPrimitives() traits
  may not block.

BUG=659191
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation
==========

to

==========
Use TaskScheduler instead of WorkerPool in
navigation_entry_screenshot_manager.cc.

The following traits are used:

Priority: Inherited (default)
  The priority is inherited from the calling context (i.e. TaskTraits
  are initialized with the priority of the current task).

Shutdown behavior: CONTINUE_ON_SHUTDOWN
  Tasks posted with this mode which have not started executing before
  shutdown is initiated will never run. Tasks with this mode running at
  shutdown will be ignored (the worker will not be joined).

  Note: Tasks that were previously posted to base::WorkerPool should
  use this shutdown behavior because this is how base::WorkerPool
  handles all its tasks.

Does Not Block (default):
  Tasks without the MayBlock() and WithBaseSyncPrimitives() traits
  may not block.

BUG=659191
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation

Review-Url: https://codereview.chromium.org/2604343002
==========

[commit-bot: I haz the power, 2017-01-04 04:28:18]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2017-01-04 04:33:49]

Description was changed from

==========
Use TaskScheduler instead of WorkerPool in
navigation_entry_screenshot_manager.cc.

The following traits are used:

Priority: Inherited (default)
  The priority is inherited from the calling context (i.e. TaskTraits
  are initialized with the priority of the current task).

Shutdown behavior: CONTINUE_ON_SHUTDOWN
  Tasks posted with this mode which have not started executing before
  shutdown is initiated will never run. Tasks with this mode running at
  shutdown will be ignored (the worker will not be joined).

  Note: Tasks that were previously posted to base::WorkerPool should
  use this shutdown behavior because this is how base::WorkerPool
  handles all its tasks.

Does Not Block (default):
  Tasks without the MayBlock() and WithBaseSyncPrimitives() traits
  may not block.

BUG=659191
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation

Review-Url: https://codereview.chromium.org/2604343002
==========

to

==========
Use TaskScheduler instead of WorkerPool in
navigation_entry_screenshot_manager.cc.

The following traits are used:

Priority: Inherited (default)
  The priority is inherited from the calling context (i.e. TaskTraits
  are initialized with the priority of the current task).

Shutdown behavior: CONTINUE_ON_SHUTDOWN
  Tasks posted with this mode which have not started executing before
  shutdown is initiated will never run. Tasks with this mode running at
  shutdown will be ignored (the worker will not be joined).

  Note: Tasks that were previously posted to base::WorkerPool should
  use this shutdown behavior because this is how base::WorkerPool
  handles all its tasks.

Does Not Block (default):
  Tasks without the MayBlock() and WithBaseSyncPrimitives() traits
  may not block.

BUG=659191
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation

Committed: https://crrev.com/9b818f0b639e940db0167e82e0bc071852d30dc0
Cr-Commit-Position: refs/heads/master@{#441316}
==========

[commit-bot: I haz the power, 2017-01-04 04:33:50]

Patchset 1 (id:??) landed as
https://crrev.com/9b818f0b639e940db0167e82e0bc071852d30dc0
Cr-Commit-Position: refs/heads/master@{#441316}