On Thu, Sep 18, 2014 at 5:35 AM, Nageswara rao Gurram < nageshgurra...@gmail.com> wrote:
> As the traffic is increasing shared memory in parent is increasing , thats > what puzzling me ! If childs write into shared of parent, then it should > come into private of child(copy on write) but why shared of parent is > increasing? (correct me if i am wrong) > OR is it work like, OS always shows copied pages of parent's shared in its > shared dirty memory(in smaps) even if it internally maintains private of > each child in that ? > I still don't think that writing to that memory in the child process is increasing the size of the parent process. Instead, I think that as the parent serves more requests, it grows in size, and new child processes that get forked from the now larger parent process are also larger. The question is, what is making your parent process grow? It might be another HTTPD module (i.e. not mod_perl), or it might be something in your configuration that is causing it to run some code in the parent. I think others have reported growth in the parent from certain compile options as well, but that may have been just on mod_perl 1. I notice that the private_dirty on your active site is not much higher than on your backup site, which means the child processes are not really using much more memory. Most of the increased size is shared, so not using up real RAM. - Perrin
