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[[!tag open_issue_gnumach]]
# IRC, freenode, #hurd, 2012-07-05
<pinotree> braunr: wrt to mach: it seems to me it ticks every 10ms or so,
it is true?
<braunr> yes
<braunr> and it's not preemptible
[[microkernel/mach/gnumach/preemption]].
<pinotree> braunr: that means a gnumach kernel currently has a maximum
uptime of almost 500 days
<braunr> pinotree: what do you mean ?
<pinotree> there's an int (or uint, i don't remember) variable that keeps
the tick count
<braunr> yes the tick variable should probably be a 64-bits type
<braunr> or a struct
<braunr> but the tick count should only be used for computation on "short"
delays
<braunr> and it should be safe to use it even when it overflows
<braunr> it's not the wall clock
<pinotree> i found that when investigating why the maximum timeout for a
mach_msg is like INT_MAX >> 2 (or 4) or something like that, also due to
the tick count
<braunr> iirc, in linux, they mostly use the lower 32-bits on 32-bits
architecture, updating the 32 upper only when necessary
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