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    <p>First of all, I agree with the previous posters and commenters - normally, you shouldn't be getting segfaults from this situation, and a proper fix is figuring out why it segfaults and correcting (could very well be a library bug as Jonathan said).</p> <p>HOWEVER, to answer your direct technical question, you can NOT recover a Perl interpreter (or any other program for that mater) once it segfaults. You wouldn't WANT to anyway - it is likely in a messy state. </p> <p>Therefore you solve your problem via a "backup" mechanism of a second process ready to pick up the shattered pieces and make sure that the show goes on, as follows:</p> <ul> <li><p>Just prior to attempted DB connection, you fork off a child process.</p> <p>Please note that you may need to daemonize the child process right after forking, as the parents death can kill the child. It's ~2am so my brain's too asleep to be sure whether it's the case or not. If that's the case, daemonization was covered numerous times on SO.</p></li> <li><p>The parent process attempts the DB connection, <strong>timed out</strong> by a standard Perl alarm (set to, say 10 seconds or whatever you want).</p></li> <li><p>If the connection was successful, it sends a signal to a child to indicate that DB connection is OK, and the parent code can proceed as usual.</p> <p>If the connection fails, the parent either coredumps, or issues a <code>die</code> assuming the connection failed in non-coredump way or timed out.</p></li> <li><p>The child process, right after forking, sets the signal handler to catch the parent's "DB connection successful" signal, and then sets the alarm for 10+<em>epsilon</em> seconds.</p></li> <li><p>If the child process catches the parent's "DB connection successful" signal, the child process dies.</p></li> <li><p>On the other hand, if the child process alarm handler is triggered, it means the parent couldn't connect to DB. Therefore, the child process sends a signal to parent "I am about to do the fail-over"; and then execute the fail-over logic as needed</p></li> </ul> <p>The above logic is very rough, it may need to be refined to deal with race conditions, perhaps by virtue of a lock obtained by both processes before using the data.</p> <p><strong>UPDATE</strong></p> <p>As noted in the comments, a variation of the above where the CHILD process tries to establish a DB connection and the parent process catches problems and acts as a fall-back may be somewhat easier to implement.</p>
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    1. POPerl5: is there a way to recover from a "Memory fault(coredump)" error?
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    1. COChaining off into child processes would confuse any monitoring scripts watching for the parent's death. It's better to fork off a child responsible for proxying requests to the database.
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    2. COIncidentally, there's code on CPAN that could be adapted for this already: http://search.cpan.org/~timb/DBI-1.616/lib/DBI/ProxyServer.pm
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    3. COthanks for the reply. It was a problem with the special Perl version I was using: 5.8.4 will cause this problem. Switching to 5.10 solves this problem. but interestingly, some colleague also suggested me to build a wrapper around the original script.
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