I've started encountering a weird problem: roughly one in three times, something will crash when I try to log in, and bounce me back to the login manager (slim in my case). When I look in .xsession-errors, I can see:

XIO:  fatal IO error 4 (Interrupted system call) on X server ":0.0"
      after 8690 requests (8690 known processed) with 0 events remaining.
XIO:  fatal IO error 11 (Resource temporarily unavailable) on X server ":0.0"
      after 2823 requests (6 known processed) with 0 events remaining.
lxpolkit: Fatal IO error 11 (Resource temporarily unavailable) on X server :0.0.
X connection to :0.0 broken (explicit kill or server shutdown).
X connection to :0.0 broken (explicit kill or server shutdown).
X connection to :0.0 broken (explicit kill or server shutdown).

But I'm not sure what this means or how to debug further.  Here's the full .xsession-errors 

Any help would be appreciated.
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