Increase buffer size in CronetFixedModeOutputStream to 16kB

Increase buffer size in CronetFixedModeOutputStream to 16kB

BUG=606924
Committed: https://crrev.com/30bb2b5092b297b6ed4c4aa669bb562165e680b4
Cr-Commit-Position: refs/heads/master@{#390774}

[xunjieli, 2016-04-27 20:18:56]

Description was changed from

==========
Increase buffer size in CronetFixedModeOutputStream to 16kB

BUG=
==========

to

==========
Increase buffer size in CronetFixedModeOutputStream to 16kB

BUG=606924
==========

[xunjieli, 2016-04-27 20:28:03]

Patchset #1 (id:1) has been deleted

[xunjieli, 2016-04-27 20:28:18]

xunjieli@chromium.org changed reviewers:
+ pauljensen@chromium.org

[xunjieli, 2016-04-27 20:28:18]

Paul, PTAL. Thanks!

[pauljensen, 2016-04-29 11:09:12]

lgtm.  A couple notes:
1. would be nice to see if this improves the performance by running my benchmark
app (./components/cronet/android/test/javaperftests/run.py)
2. the comment mentions the cost of compact().  We could avoid this by not
compacting and just always copying into the remaining space in the buffer,
right?

[xunjieli, 2016-04-29 21:02:00]

On 2016/04/29 11:09:12, pauljensen wrote:
> lgtm.  A couple notes:
> 1. would be nice to see if this improves the performance by running my
benchmark
> app (./components/cronet/android/test/javaperftests/run.py)

I synced telemetry to a version that worked (thanks to digging up the cause). I
ran it a couple of times with and without the patch. The data is odd because we
are seeing bigger improvement for small uploads. I don't think the change should
matter at all for small uploads. There is a lot of variance too.

Up___Q_4_1_CronetHUC__   7680.00 ms -> 7574.00 ms   ~1% improvement
Up___Q_4_4_CronetHUC__   6944.00 ms -> 6867.00 ms   ~1% improvement
Up___H_1000_1_CronetHUC__ 4729.00 ms -> 4518.00 ms  ~4% improvement
Up___H_1000_4_CronetHUC__ 2652.00 ms -> 2532.00 ms  ~4% improvement
Other benchmarks are about the same.

> 2. the comment mentions the cost of compact().  We could avoid this by not
> compacting and just always copying into the remaining space in the buffer,
> right?
Talked offline. I can investigate the use of a circular buffer instead of
compacting as a follow-up.

[xunjieli, 2016-04-29 21:02:32]

The CQ bit was checked by xunjieli@chromium.org

[commit-bot: I haz the power, 2016-04-29 21:03:00]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1928753002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1928753002/20001

[commit-bot: I haz the power, 2016-04-29 21:53:46]

Description was changed from

==========
Increase buffer size in CronetFixedModeOutputStream to 16kB

BUG=606924
==========

to

==========
Increase buffer size in CronetFixedModeOutputStream to 16kB

BUG=606924
==========

[commit-bot: I haz the power, 2016-04-29 21:53:47]

Committed patchset #1 (id:20001)

[commit-bot: I haz the power, 2016-04-30 17:29:24]

Patchset 1 (id:??) landed as
https://crrev.com/30bb2b5092b297b6ed4c4aa669bb562165e680b4
Cr-Commit-Position: refs/heads/master@{#390774}

[commit-bot: I haz the power, 2016-04-30 18:02:52]

Description was changed from

==========
Increase buffer size in CronetFixedModeOutputStream to 16kB

BUG=606924
==========

to

==========
Increase buffer size in CronetFixedModeOutputStream to 16kB

BUG=606924

Committed: https://crrev.com/30bb2b5092b297b6ed4c4aa669bb562165e680b4
Cr-Commit-Position: refs/heads/master@{#390774}
==========