[SyncFS] CountDirtyTracke() does not run a full scan

[SyncFS] CountDirtyTracke() does not run a full scan.

It reduces disk I/O cost on counting dirty trackers.


BUG=347425
TEST=./unit_tests --gtest_filter="MetadataDatabase*"

Committed: https://crrev.com/a38fa22d030b7688544a5f41f4fc9a5b5dfe22c2
Cr-Commit-Position: refs/heads/master@{#293447}

[peria, 2014-09-04 06:36:01]

Patchset #1 (id:1) has been deleted

[peria, 2014-09-04 06:44:10]

Patchset #1 (id:20001) has been deleted

[peria, 2014-09-04 06:46:02]

peria@chromium.org changed reviewers:
+ nhiroki@chromium.org, tzik@chromium.org

[peria, 2014-09-04 06:46:03]

PTL

[tzik, 2014-09-04 06:48:44]

Can we just hold it on memory..?

[peria, 2014-09-04 06:50:41]

On 2014/09/04 06:48:44, tzik wrote:
> Can we just hold it on memory..?

Yes, we can.
Though, it needs to sweep all dirty tracker entries on construction.

I'll update this CL.

[peria, 2014-09-04 06:59:42]

On 2014/09/04 06:50:41, peria wrote:
> On 2014/09/04 06:48:44, tzik wrote:
> > Can we just hold it on memory..?
> 
> Yes, we can.
> Though, it needs to sweep all dirty tracker entries on construction.
> 
> I'll update this CL.

Done.

[tzik, 2014-09-04 07:05:22]

lgtm

[nhiroki, 2014-09-04 07:11:27]

lgtm

[peria, 2014-09-04 07:12:18]

The CQ bit was checked by peria@chromium.org

[commit-bot: I haz the power, 2014-09-04 07:13:34]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/peria@chromium.org/536343002/80001

[commit-bot: I haz the power, 2014-09-04 08:06:22]

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

[commit-bot: I haz the power, 2014-09-04 08:06:23]

Try jobs failed on following builders:
  android_clang_dbg_recipe on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/android_clang_d...)

[peria, 2014-09-04 08:07:01]

The CQ bit was checked by peria@chromium.org

[commit-bot: I haz the power, 2014-09-04 08:08:00]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/peria@chromium.org/536343002/80001

[commit-bot: I haz the power, 2014-09-04 08:53:53]

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

[commit-bot: I haz the power, 2014-09-04 08:53:53]

Try jobs failed on following builders:
  android_clang_dbg_recipe on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/android_clang_d...)

[peria, 2014-09-04 09:30:44]

The CQ bit was checked by peria@chromium.org

[commit-bot: I haz the power, 2014-09-04 09:32:18]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/peria@chromium.org/536343002/80001

[commit-bot: I haz the power, 2014-09-04 20:28:55]

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

[commit-bot: I haz the power, 2014-09-04 20:28:55]

Try jobs failed on following builders:
  win_gpu_triggered_tests on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/win_gpu_triggered...)

[peria, 2014-09-05 01:57:55]

The CQ bit was checked by peria@chromium.org

[commit-bot: I haz the power, 2014-09-05 02:00:24]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/peria@chromium.org/536343002/80001

[commit-bot: I haz the power, 2014-09-05 03:03:31]

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

[commit-bot: I haz the power, 2014-09-05 03:03:32]

Try jobs failed on following builders:
  win_gpu_triggered_tests on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/win_gpu_triggered...)

[peria, 2014-09-05 03:29:32]

The CQ bit was checked by peria@chromium.org

[commit-bot: I haz the power, 2014-09-05 03:30:13]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/peria@chromium.org/536343002/80001

[peria, 2014-09-05 03:37:37]

The CQ bit was checked by peria@chromium.org

[commit-bot: I haz the power, 2014-09-05 03:39:46]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/peria@chromium.org/536343002/100001

[commit-bot: I haz the power, 2014-09-05 05:05:45]

Committed patchset #4 (id:100001) as b23dbc0aea7ed99b06a5cdddb3349c258b295347

[commit-bot: I haz the power, 2014-09-10 03:37:05]

Patchset 4 (id:??) landed as
https://crrev.com/a38fa22d030b7688544a5f41f4fc9a5b5dfe22c2
Cr-Commit-Position: refs/heads/master@{#293447}