Bug 61107 - AllocationEvent's come before associated VTable event
Summary: AllocationEvent's come before associated VTable event
Status: RESOLVED INVALID
Alias: None
Product: Runtime
Classification: Mono
Component: Profiler ()
Version: master
Hardware: PC Mac OS
: --- normal
Target Milestone: ---
Assignee: Alex Rønne Petersen
URL:
Depends on:
Blocks:
 
Reported: 2017-12-15 13:34 UTC by Rodrigo Moya
Modified: 2017-12-15 15:28 UTC (History)
3 users (show)

Tags:
Is this bug a regression?: ---
Last known good build:

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Status:
RESOLVED INVALID

Description Rodrigo Moya 2017-12-15 13:34:06 UTC
In mono master (5.11), the MLPDs produced by the runtime profiler seem to have one problem, only happening for a few "System.RuntimeType" allocations that seem to happen at the beginning of the application. The series of events is:

(Messages obtained via adding debugging console output to Xamarin.Profiler on a v15 MLPD where the problem was seen)
Buffer ID's are the buffer's TimeBase field, and the 2nd number is the timestamp of the specific event:

1. ClassLoad event:
   The culprit is System.RuntimeType at buffer 19250786083136 at 19250788456173
2. Several Allocation events for objects of that type, without any stack trace:
   No backtrace at buffer 19250786083136 at 19250789353288
   No backtrace at buffer 19250786083136 at 19250789359463
   No backtrace at buffer 19250786083136 at 19250789362233
   No backtrace at buffer 19250786083136 at 19250789363302
   No backtrace at buffer 19250786083136 at 19250789364130
3. VTable event for the unknown-till-now VTablePointer:
   Got unknown VTable for class 2072191896 at buffer 19250786083136 at 19250789365557

All events are in the same buffer, and it is not an ordering problem because of the timestamp sorting in SyncPoint, as the events have different timestamps
Comment 1 Rodrigo Moya 2017-12-15 15:28:23 UTC
Moving to GH