[OpenSIPS-Users] Not enough memory to sync cluster data

[Vitalii Aleksandrov]

> This seems to be more clean, efficient, and if you don't need it, the 
> OS will not even allocate it (due to the demand-paging mechanism). So 
> I don't see where you reservations for setting a higher value of the 
> -M parameter come from.
>
> Best regards,
> Răzvan
>
Just my 2 cents about PKG mem. Indeed OS will not allocate all requested 
PKG mem at the strartup. After a while if sync mechanism continues to 
work continuously all worker processes will be involved at least once in 
a syncing process (send or receive big amount of data). That means that 
all processes will try to init that memory and OS will finally map 
requested virtual memory to psychical one. When the sync is finished and 
after pkg_free() called that memory becomes free and reusable from the 
process point of view, but if I recall correctly how the memory manager 
works (at least worked in kamailio) those chunks will be just marked as 
free in internal data structure but never returned back to the OS. To 
make long story short in the end after a while OS will have to really 
allocate RAM for all opensips worker processes if all of them are 
involved in proto_bin processing (not sure about it).
Please correct me if I'm wrong.