Re: [exim] option -MCd

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Author: Jeremy Harris
Date:  
To: exim-users
Subject: Re: [exim] option -MCd
On 30/06/2020 16:01, Marc Haber via Exim-users wrote:
> A contributor on the bug report says:
> |I am pretty sure that the problem is caused by the commit 6906c131d1d07d07831f8fbabae6290a3cba6ca3                      
> |(Use a monotonic clock, if available, for ID generation).                                                               
> |The change contains measuring of the difference between CLOCK_MONOTONIC and realtime once                               
> |at startup (exim_clock_init), but as far as I understand CLOCK_MONOTONIC                                                
> |on Linux does not increase during suspend/hibernate (possibly wrognly [1]),                                             
> |so the difference grows then, unaccounted for.                                                                          
> |                                                                                                                        
> |[1]: https://stackoverflow.com/a/3527632/1236045                                                                        

>
> Is this the possible cause of the issue showing up on at least three
> Debian systems since we upgraded to exim 4.94?


Aha. Yes, because Linux does not adhere to Posix for CLOCK_MONOTONIC
over a suspend, every message will get a delay after final-dot for the
aggregate suspend time since the exim process (the daemon, for smtp
receptions) was started.

This is obviously untenable and Exim must workaround the
standards-deficient platform. Fix upcoming.

Frank - if you see this, could a suspend have been involved
in your cases?
--
Cheers,
Jeremy