[Varnish] #1750: Fail more gracefully on -l >= 4GB

[Varnish]

#1750: Fail more gracefully on -l >= 4GB
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 Reporter:  geoff                |       Type:  defect
   Status:  new                  |   Priority:  low
Milestone:  Varnish 4.0 release  |  Component:  varnishd
  Version:  4.0.3                |   Severity:  minor
 Keywords:                       |
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 Varnish cannot run with a VSM file size of 4GB or more -- as discussed
 with Martin on IRC, the VSM API cannot accommodate sizes that large (for
 example due to unsigned ints as offsets).

 But the varnishd command succeeds with -l 4g -- the management process
 starts, and then the child process fails an assert. So the invocation
 appears to be normal, although Varnish fails almost immediately.

 On my system, there was a message in /var/log/messages indicating failure
 of the child due to SIGABRT, but there was no core dump (although I always
 get them otherwise). And since the management process also stopped, there
 was no panic message, so there was nothing useful to diagnose the problem.

 I suggest checking -l against the maximum on invocation, and failing right
 away to stderr.

-- 
Ticket URL: <https://www.varnish-cache.org/trac/ticket/1750>
Varnish <https://varnish-cache.org/>
The Varnish HTTP Accelerator