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Hi Sven,<br>
<br>
On 18/11/10 17:00, Sven Schulz wrote:
<blockquote cite="mid:C90AA9A0.21C2E%25svens@psu.edu" type="cite">
<title>Private Memory vs Shared Memory</title>
<font face="Calibri, Verdana, Helvetica, Arial"><span
style="font-size: 11pt;">Just a few generic questions: What is the
difference between shared and private memory in opensips? </span></font></blockquote>
Private memory is the memory used by one process, while shared memory
is memory accessible by all processes (it is an IPC method, see
<a class="moz-txt-link-freetext" href="http://en.wikipedia.org/wiki/Shared_memory">http://en.wikipedia.org/wiki/Shared_memory</a>). The private memory is used
for temporary storages required for certain processing by a process,
while the shared memory is used to store data that must be accessible
by all processes.<br>
<blockquote cite="mid:C90AA9A0.21C2E%25svens@psu.edu" type="cite"><font
face="Calibri, Verdana, Helvetica, Arial"><span
style="font-size: 11pt;">And how does each relate to the child
processes?</span></font></blockquote>
When you set the private memory(by editing config.h) it means that each
process will have that amount of private memory. What you set with -m
parameter when starting opensips is the entire chunk of shared memory
that will be used. OpenSIPS has an internal memory management system -
and it allocates all the required memory at startup - so
no_of_children*pkg_mem private memory and shm_mem shared memory and
from these chuncks allocated at startup it gives to the processes
pieces when they ask for it with pkg_malloc or shm_malloc.<br>
<blockquote cite="mid:C90AA9A0.21C2E%25svens@psu.edu" type="cite"><font
face="Calibri, Verdana, Helvetica, Arial"><span
style="font-size: 11pt;"> Also, is there a good guideline to what
these should be set in relation to how much RAM is installed.<br>
</span></font></blockquote>
You must have at least RAM as no_of_children*pkg_mem + shm_mem.<br>
<br>
Regards,<br>
<pre class="moz-signature" cols="72">--
Anca Vamanu
<a class="moz-txt-link-abbreviated" href="http://www.voice-system.ro">www.voice-system.ro</a></pre>
<br>
<blockquote cite="mid:C90AA9A0.21C2E%25svens@psu.edu" type="cite"><font
face="Calibri, Verdana, Helvetica, Arial"><span
style="font-size: 11pt;">Thanks,<br>
<br>
</span></font><span style="font-size: 11pt;"><font
face="Optima, Times New Roman">Sven Schulz<br>
Penn State University<br>
Telecommunications and Network Services<br>
814.865.6116<br>
sip:<a moz-do-not-send="true" href="sven@psu.edu">sven@psu.edu</a></font></span><br>
</blockquote>
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