What is the most efficient way to connect my application on one VM to my Postgres DB on another VM?

I upgraded a server with a Rails application to Ubuntu 12.04 from 10.04 and cannot connect to Postgresql database now...

Here is the error message from Rails app:

could not connect to server: No such file or directory Is the server running locally and accepting connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"

Also the pg_ctl start is not recognized as a command.

EDIT:

Tur

For testing a networking application, I have written an asio port "proxy": it listens on a socket for the application client activity and sends all incoming packets to another socket where it is listened to by the application server, and back.

Now when either the application or the server disconnect for various reasons, the "proxy" usually gets an EOF but sometimes it receives a "connection reset

I have currently created a simple tcp socket client application that sends and receives messages from a dotnet server application I have created. The application itself actually works however there are a few things I would like to know if they are possible or not.

mmap provides a way for process to write to and read from memory, there is not need for process to switch to kernel mode when to write/read. Less system calling means more efficient. Other methods for inter-process communication ,such as pipe, socket, usually have to switch to kernel mode when do read/write. So, as I can see, mmap is the most efficient method for inter-process communication.

I am trying to the robustness of my application and would like to close a connected socket in OS X without killing the application or the network connection(I want other sockets to stay open). Can I do this with ipfw? If so how?

We are developing a network application based on C/S, in this application the server needs to transfer files to clients and sometimes receive files from clients. So in the server application, for every client it needs to create a control socket and many transfer sockets.

My question is how we can create and define a socket as role of control socket or transfer socket?

hello i have a client socket application, that connect at the same time, with more than 5000 server with tcpip in linux, but when i open the socket connection, almost all connections, retrieve the error Operation now in progress.

Here my client socket connect code: how can i doing a good thousands simultaneously socket conecction at the same time??? sorry for my english. here my code :

struct so

I have a Xeon E3-1230 processor, which has 4 physical cores, but has hyperthreading so an operating system running on it sees 8 logical cores.

I installed VMware ESXi and am creating virtual machines to run on it.

I'm running scientific software (WRF-NMM, atmosphere simulation, weather prediction). On all computers I used it, job running times of run cycles were consistent. All those machines were one socket, desktop machines. However, on dual socket computer I have VERY uneven running times. For example, my job running times equals anything between 2hr 50min to more than 5 hours.