Adjoint threads, discontinuity and time delta: software trace pattern cooperation

Here is one of the first case studies in pattern-driven software trace analysis. A user starts printing but nothing comes out. However, if the older printer driver is installed everything works as expected. We suspect that print spooler crashes if the newer printer driver is used. Based on known module name in ETW trace we find PID for print spooler process (19984) and immediately see discontinuity in the trace with the large time delta between the last PID message and the last trace statement (almost 4 minutes): 

No   Source        PID   TID   Time         Message
712  \src\print\ui 19984 16200 12:22:31.571 PropertySheet returns 1
[… no messages for PID 19984 …]
5103 \src\mgmt   1292  7604  12:26:11.659 WaitAction

If we select the adjoint thread of source \src\print\driver (in other words, filter only its messages) we would see discontinuity with the similar time delta. We know that printer driver runs in print spooler context. However, PID had changed and that means print spooler was restarted (perhaps after a crash):

No   Source            PID   TID   Time         Message
557  \src\print\driver 19984 16200 12:22:28.069 DisableDevice returns
[… discontinuity for \print\driver …]
1462 \src\print\driver 10828 17584 12:26:03.854 DllMain

- Dmitry Vostokov @ + -

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