Hi developers, I have a question between the numbers of cosd and memory cache in a server. Here is my environment.... I got 15 servers as OSDes and each one has 8 cores CPU, 16GB RAM and 1TB*12 Disks. I only have 1 MDS and 3 MONs(4 servers as total) and the specifications are the same as OSDes. I know that each cosd process would consume some memories and so does data transmission. In my environment, I set 10 cosd processes on each server. My assumption is that based on my scenario, the buffer used by each cosd would be (Total RAM-N*cosd used)/N .....(N is the number of cosd) That is,if I assume each cosd would use 200MB RAM, so each cosd would have about (16GB-10*200MB)/10 = 1.4GB RAM to use as buffer. I don't know if my assumption is right or not. Please correct me if it's wrong. "IF" my theory is right, would it be better if I set the number of cosd to be less? What I mean is that when I get less cosd process, each cosd would have more memories to use as buffer and it's better? In other words, based on my environment with 12 disks in a server, how many numbers of cosd should I set to get the best usage of memories? I know the more RAM, the better performance. But are there some kind of formulas to calculate the proportions between cosd and RAM? Thanks in advance! -- Best Regards, Sylar Shen -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
