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<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">Hello,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">I have been testing syslog-ng under different scenarios and I noticed that when syslog-ng is trying to connect to an external syslog-ng server, it exhibits what could be called
a memory leak.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">Let me explain how I am setting up my test. I have a syslog-ng client running collecting logs from a file (source) and sending them to an external syslog-ng server over TCP
(destination). If the syslog-ng server is online, the syslog-ng client daemon process virtual memory does not increase. Now, when I kill the syslog-ng server, the syslog-ng client daemon process starts to request more and more virtual memory.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">Here are the details:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">I started both the syslog-ng client and server and started to send logs from the client to the server. At this point, the syslog-ng client daemon maintained its VmSize equal
to 7144 Kbytes. This condition was stable for 4 hours while the server was online.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">Then, after 4 hours, I killed the syslog-ng server. As soon as I did that, the syslog-ng client daemon virtual memory size started to increate every few seconds. Started
at 7144 Kbytest and after 4 hours VmSize was equal to 7752 Kbytes. So it grew 608 Kbytes over the next 4 hours.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">Finally, after the 4 hours I just mentioned, I restarted the syslog-ng server. All the logs that had not been sent for 4 hours were transmitted to the syslog-ng server in
a few seconds. At this point, the syslog-ng client daemon virtual memory stopped growing and stayed stable for 4 hours.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">I think that this behavior may be related to the logs generated every time the client tries to reconnect with the server. By the way, the client time_reopen configuration
was set to 15 seconds.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">I am worried that over a long long period of time, if the syslog-ng server is not online, the syslog-ng client daemon may be killed by the OS for using too much memory.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">Please let me know if you have any ideas how to fix this problem, thank you.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
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