[Telemetry] Add an option to log timestamp.

[Telemetry] Add an option to log timestamp.

With "--log_time" optional arg, we can see each logged event's
timestamp to know how long does a task spend.

BUG=None
TEST=manual ./run_benchmark with "-v --log_time" args added.

Committed: https://crrev.com/83d444db263917c397f8adeb7040a6b1349c5707
Cr-Commit-Position: refs/heads/master@{#330337}

[deanliao, 2015-04-10 04:50:30]

deanliao@chromium.org changed reviewers:
+ nednguyen@google.com

[deanliao, 2015-04-10 04:50:30]

With --log_time, we can have a clear picture how long does an action take.

[nednguyen, 2015-04-10 16:29:28]

nednguyen@google.com changed reviewers:
+ dtu@chromium.org

[nednguyen, 2015-04-10 16:29:28]

You'd better off by using python trace by Nat.

[nednguyen, 2015-04-10 16:31:45]

On 2015/04/10 16:29:28, nednguyen wrote:
> You'd better off by using python trace by Nat.

https://github.com/natduca/py_trace_event

[deanliao, 2015-05-14 07:37:14]

On 2015/04/10 16:31:45, nednguyen (slow review) wrote:
> On 2015/04/10 16:29:28, nednguyen wrote:
> > You'd better off by using python trace by Nat.
> 
> https://github.com/natduca/py_trace_event

Good to know py_trace_event. A great tool!

However, it needs to add decorators everywhere. For the case I just want to see
a timestamp in Telemetry running log, don't you think this CL's approach is more
appropriate.

[nednguyen, 2015-05-14 16:09:33]

On 2015/05/14 07:37:14, deanliao wrote:
> On 2015/04/10 16:31:45, nednguyen (slow review) wrote:
> > On 2015/04/10 16:29:28, nednguyen wrote:
> > > You'd better off by using python trace by Nat.
> > 
> > https://github.com/natduca/py_trace_event
> 
> Good to know py_trace_event. A great tool!
> 
> However, it needs to add decorators everywhere. For the case I just want to
see
> a timestamp in Telemetry running log, don't you think this CL's approach is
more
> appropriate.

We don't want to keep supporting more telemetry command line flags. If this is
useful (I think it's), we probably can just make this a default thing in
telemetry?

[deanliao, 2015-05-15 03:31:37]

On 2015/05/14 16:09:33, nednguyen (slow review) wrote:
> On 2015/05/14 07:37:14, deanliao wrote:
> > On 2015/04/10 16:31:45, nednguyen (slow review) wrote:
> > > On 2015/04/10 16:29:28, nednguyen wrote:
> > > > You'd better off by using python trace by Nat.
> > > 
> > > https://github.com/natduca/py_trace_event
> > 
> > Good to know py_trace_event. A great tool!
> > 
> > However, it needs to add decorators everywhere. For the case I just want to
> see
> > a timestamp in Telemetry running log, don't you think this CL's approach is
> more
> > appropriate.
> 
> We don't want to keep supporting more telemetry command line flags. If this is
> useful (I think it's), we probably can just make this a default thing in
> telemetry?

Agreed. Make it default

[nednguyen, 2015-05-15 04:29:50]

lgtm

[deanliao, 2015-05-18 06:37:19]

The CQ bit was checked by deanliao@chromium.org

[deanliao, 2015-05-18 06:37:21]

The CQ bit was unchecked by deanliao@chromium.org

[deanliao, 2015-05-18 06:37:32]

The CQ bit was unchecked by deanliao@chromium.org

[deanliao, 2015-05-18 06:41:14]

The CQ bit was checked by deanliao@chromium.org

[commit-bot: I haz the power, 2015-05-18 06:41:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1079443002/20001

[commit-bot: I haz the power, 2015-05-18 08:58:28]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-05-18 11:34:03]

Patchset 2 (id:??) landed as
https://crrev.com/83d444db263917c397f8adeb7040a6b1349c5707
Cr-Commit-Position: refs/heads/master@{#330337}