Half of events with User ID (uid) do not show up in reports

[GoogleCodeExporter]

Name of affected component: Measurement Protocol

Issue summary:
If I set the uid field on events then I see all events in the real time report. 
But if the uid field is set only about half the events show up in the behavior 
report. If I remove the uid field all events show up in the behavior reports. I 
have tried a number of different values for uid, including sending all with the 
same uid and in every case only about half the events appear in the report.

Steps to reproduce issue:
1. Using measurement protocol directly, report 100 events with the uid value set
2. Observe all 100 events in the Real-Time events view
3. Wait
4. Look at the Behavior/Events/Top Events report. Only about half the events 
will be there.

Expected output:
100 events in the Behavior/Events/Top Events report

Actual results:
About 50 events in the Behavior/Events/Top Events report (actual number varies)

Original issue reported on code.google.com by ransomri...@gmail.com on 16 Oct 2014 at 4:02

[GoogleCodeExporter]

[deleted comment]

[GoogleCodeExporter]

It seems that if you send both uid and cid, Google would validate your cid and 
if cid be not compatible with UUID (version 4), for most cases just about half 
of the request could be accepted.  
But If you just send cid, all of the request would be accepted.

Actually, since uid is an optional parameter and Google seems to use cid to 
track a particular session, I think there's little difference whether to send 
uid or not. 

So, you may try not to send uid 
or you may try to change your cid to UUID (Version 4) according to Google's 
Document.

Original comment by maxw...@njuopen.com on 10 Dec 2014 at 1:54

[GoogleCodeExporter]

We are having the same issue when passing both uid and cid to GA Tracking tool 
via API  Call. In our case (as of now) we are passing uid and cid as same 
unique ID e.g. &uid=4151&cid=4151

Is this an issue from Google Analytics or this is an expected behavior and we 
need to remove uid to make it work ?

Your response is highly appreciated..

Thanks

Original comment by shyampga...@gmail.com on 13 Jan 2015 at 4:49

[GoogleCodeExporter]

Not sure but may be this issue is related
https://code.google.com/p/analytics-issues/issues/detail?id=570

Original comment by zigzag....@gmail.com on 16 Jan 2015 at 10:16