QUIC - Added a histogram to count the number of current active sessions

QUIC - Added a histogram to count the number of current active sessions
before we add a new session to the active sessions.

R=jar@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=274356

[ramant (doing other things), 2014-06-02 02:08:03]

Hi Jim and Ryan,
  Added a histogram to count the #of active sessions that are there when we add
a new session to the active_sessions (we do this when QUIC session is not
pooled).

  This is to get data if we pool sessions more aggressively, how much benefit
could we get (per discussion with jar).

  Did I implement what you had in mind? PTAL.

thanks
raman

[Ryan Hamilton, 2014-06-02 15:30:48]

Please also edit histograms.xml as part of this CL.

[ramant (doing other things), 2014-06-02 17:05:21]

Added Net.QuicActiveSessions to histograms.xml. 

Could the description be "Number of other live active sessions".

thanks,
raman

[Ryan Hamilton, 2014-06-02 17:10:51]

lgtm

https://codereview.chromium.org/307993011/diff/20001/tools/metrics/histograms...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/307993011/diff/20001/tools/metrics/histograms...
tools/metrics/histograms/histograms.xml:13512: +    The number of active QUIC
sessions before we add a new QUIC session to
how 'bout: "... before we activate a new QUIC session"?

[ramant (doing other things), 2014-06-02 17:16:28]

https://codereview.chromium.org/307993011/diff/20001/tools/metrics/histograms...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/307993011/diff/20001/tools/metrics/histograms...
tools/metrics/histograms/histograms.xml:13512: +    The number of active QUIC
sessions before we add a new QUIC session to
On 2014/06/02 17:10:51, Ryan Hamilton wrote:
> how 'bout: "... before we activate a new QUIC session"?

Done.

[ramant (doing other things), 2014-06-02 17:16:32]

The CQ bit was checked by rtenneti@chromium.org

[commit-bot: I haz the power, 2014-06-02 17:17:35]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/rtenneti@chromium.org/307993011/40001

[commit-bot: I haz the power, 2014-06-02 19:40:04]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  chromium_presubmit on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/chromium_presubmit/bu...)

[ramant (doing other things), 2014-06-02 19:44:04]

Hi Jim, Isherman,
  Would appreciate if you could take a look at histograms.xml (for OWNER's
approval).

thanks
raman

[commit-bot: I haz the power, 2014-06-02 19:46:42]

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

[commit-bot: I haz the power, 2014-06-02 19:46:42]

Try jobs failed on following builders:
  chromium_presubmit on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/chromium_presubmit/bu...)

[jar (doing other things), 2014-06-02 22:22:02]

lgtm

[commit-bot: I haz the power, 2014-06-02 22:34:09]

Change committed as 274356