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Hello List,

I believe, I found a bug in ndo2db.c in ndoutils.

Problem is:=20
ndo2db forks a child for each accepted connection.
The Parent process calls waitpid _once_ for each received SIGCHLD.

But *nix does not guarantee the delievery of every SIGCHLD if multiple =
Signals of the same type occur.
--> increasing number of zombies.

Usually this no problem because the number of forks and waits is quite =
small and the probability of lost SIGCHLDs is even smaller (practically =
zero).
In our setup clients close the connection frequently and we have over =
500 Nagios instances reporting to one central ndo2db, which raises the =
number of forks, waits and losses of SIGCHLDs to a significant level.

This patch repeats the call to waitpid until no finished children =
(zombies) are left.

Regards,
Joey5337 / Tilo Renz

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Bug in ndoutils / ndo2db




Hello List,

I believe, I found a bug in ndo2db.c in ndoutils.

Problem is:
ndo2db forks a child for each accepted connection.
The Parent process calls waitpid _once_ for each received SIGCHLD.

But *nix does not guarantee the delievery of every SIGCHLD if multiple =
Signals of the same type occur.
--> increasing number of zombies.

Usually this no problem because the number of forks and waits is quite =
small and the probability of lost SIGCHLDs is even smaller (practically =
zero).
In our setup clients close the connection frequently and we have over =
500 Nagios instances reporting to one central ndo2db, which raises the =
number of forks, waits and losses of SIGCHLDs to a significant =
level.

This patch repeats the call to waitpid until no finished children =
(zombies) are left.

Regards,
Joey5337 / Tilo Renz





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