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<p class="MsoNormal">Hi all,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I noticed today that I’m missing something basic… I wanted to allocate some buffers that will live throughout the lifetime of the process =<br>
not associated with any specific request. I believe I’ve already done something like that in the past, and I used the cycle pool for that.<o:p></o:p></p>
<p class="MsoNormal">However, after digging a bit in the code, I found that in single process mode, if nginx is reloaded, a new cycle is created and the
<br>
old one destroyed.<o:p></o:p></p>
<p class="MsoNormal"><br>
If my understanding is correct, this has many implications far exceeding the simple question I started with…
<br>
For example, since the configuration is allocated on the cycle pool, it means that modules should not read the configuration
<br>
of the request in any asynchronous callback, because there is a chance that the configuration was already freed since the request
<br>
object was created.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I then found this issue - <a href="https://trac.nginx.org/nginx/ticket/945">
https://trac.nginx.org/nginx/ticket/945</a> so I guess that this problem is known and ignored because
<br>
‘master_process off’ is only for dev, and no need to support reload there…<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So, back to my original question… is using ngx_cycle->pool the correct way to allocate such “persistent” buffers?<o:p></o:p></p>
<p class="MsoNormal">Another option is to use ngx_alloc directly (if the process quits, it doesn’t matter…), but cycle pool sounds a bit more elegant<br>
(and won’t have valgrind report leaks…)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Eran<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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