03-11-2008
Use AIO or Thread Pool
Multiple threads can definately listen to single socket. All threads can be blocked on "select" or "poll" system-call. Now depending on number of CPU your that many number of threads will come out of select/poll system call then if its TCP you mandatory call "accept" system-call. Here only 1 thread will succeed and remaining threads will fails which again go back to select/poll system-call. Now if instead of TCP you using UDP then same above syncronization will happen at "read" system-call and remaining threads has to go back at select/poll. Pseudo code will look like
while(1) {
select(sockfd);
rs = accept(sockfd);
if(rs == -1) continue;
thread_function();
}
But from past-experience. I'd recommend you to re-design of your software with producer and worker concept. One thread will read data on socket then it will select a thread from pool and assign work to that.
From our statistics I'd say 1GHz CPU can efficiently hangle 25 complex threads only!!! And for multithreads instead of deploying higher capacity of CPU you should go for higher multi-core procerrors only!!!
10 More Discussions You Might Find Interesting
1. Programming
Hi,
I want to validate that a file is a socket file on Linux. I know I can do this using the S_ISSOCK macro, but I am not sure how to get the file descriptor for the socket file.
For example, I know that /tmp/mapping-foo is a socket file. In Python I can do something like this:
>>> import... (2 Replies)
Discussion started by: goon12
2 Replies
2. Programming
I have set the receive buffer size of socket to max.
setsockopt(sd,SOL_SOCKET, SO_RCVBUF,&max,optval);
Am reading data from the socket in a loop(say max 100 bytes per recv)
while(1)
{
int rlen=recv(sd,(void *)buf, 100 , 0);
//err handle and processing
}
Assume my process is slow... (2 Replies)
Discussion started by: johnbach
2 Replies
3. Solaris
Hi All
I have a separate thread ListenerThread having a socket listening to info broadcasted by some remote server. This is created in my main thread.
Because of requirements, once the separate thread is started I need to avoid any blocking function on the main thread. Once it comes to the... (2 Replies)
Discussion started by: manustone
2 Replies
4. Solaris
I have a query related to the functioning of poll() system call on solaris and linux platforms.
When the client is abnormally terminated, it is observed that on Linux the socket is immediately closed and the server gets ECONNREFUSED.
But in case of Solaris it is observed that the socket is not... (0 Replies)
Discussion started by: Amarjeet_7
0 Replies
5. Programming
char name;
printf ("Welcome to the server \n");
printf ("Enter user name: \n");
scanf ("%c", &name);
how can client send name to server:what should be the code?
int send ( int sid , const char ∗buffer Ptr , int len , int f l a g )
how can client receive ack from... (1 Reply)
Discussion started by: saiful_911
1 Replies
6. Programming
How to know whether socket is ready for write.
select(maxfds, (fd_set *)NULL, &writefds, NULL, &timeout);
By default socket is set for write without checking whether it would block or not? If so how do I know my FD is ready for writing. (3 Replies)
Discussion started by: satish@123
3 Replies
7. Programming
Hi all,
Can I create multiple threads using single thread_id
like
pthread_t thread_id;
pthread_create(&thread_id, NULL, &print_xs, NULL);
pthread_create(&thread_id, NULL, &print_ys, NULL);
pthread_create(&thread_id, NULL, &print_zs, NULL);
pthread_join(thread_id, NULL);
what... (2 Replies)
Discussion started by: zing_foru
2 Replies
8. IP Networking
Hello to all,
I have below function, but the thread will be bloked at the line
delete pListenSocket; // Close and delete
If I put some cpu timing switching function prior to it, then no blocking pop up.
printf("xyz\n"); // or sleep(100);
delete pListenSocket; // Close and... (1 Reply)
Discussion started by: shinypro
1 Replies
9. Solaris
I have BIND 9.8.1-P1 cache only DNS server running in Solaris 10. I have upgraded the same from 9.6.1 to 9.8.1-P1. Now i am facing "file descriptor exceeds limit (4096/4096)" error frequently on the server.
Please help me on this issue! (1 Reply)
Discussion started by: sandeep.tk
1 Replies
10. Shell Programming and Scripting
Hi,
Input
7488 7389 chr1.fa chr1.fa
3546 9887 chr5.fa chr9.fa
7387 7898 chrX.fa chr3.fa
7488 7389 chr21.fa chr3.fa
7488 7389 chr1.fa chr1.fa
3546 9887 chr9.fa chr5.fa
7898 7387 chrX.fa chr3.fa
Desired Output
7488 7389 chr1.fa chr1.fa 2
3546 9887 chr5.fa chr9.fa 2... (2 Replies)
Discussion started by: jacobs.smith
2 Replies
LEARN ABOUT LINUX
shutdown
SHUTDOWN(P) POSIX Programmer's Manual SHUTDOWN(P)
NAME
shutdown - shut down socket send and receive operations
SYNOPSIS
#include <sys/socket.h>
int shutdown(int socket, int how);
DESCRIPTION
The shutdown() function shall cause all or part of a full-duplex connection on the socket associated with the file descriptor socket to be
shut down.
The shutdown() function takes the following arguments:
socket Specifies the file descriptor of the socket.
how Specifies the type of shutdown. The values are as follows:
SHUT_RD
Disables further receive operations.
SHUT_WR
Disables further send operations.
SHUT_RDWR
Disables further send and receive operations.
The shutdown() function disables subsequent send and/or receive operations on a socket, depending on the value of the how argument.
RETURN VALUE
Upon successful completion, shutdown() shall return 0; otherwise, -1 shall be returned and errno set to indicate the error.
ERRORS
The shutdown() function shall fail if:
EBADF The socket argument is not a valid file descriptor.
EINVAL The how argument is invalid.
ENOTCONN
The socket is not connected.
ENOTSOCK
The socket argument does not refer to a socket.
The shutdown() function may fail if:
ENOBUFS
Insufficient resources were available in the system to perform the operation.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
getsockopt() , read() , recv() , recvfrom() , recvmsg() , select() , send() , sendto() , setsockopt() , socket() , write() , the Base Defi-
nitions volume of IEEE Std 1003.1-2001, <sys/socket.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol-
ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE
and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained
online at http://www.opengroup.org/unix/online.html .
IEEE
/The Open Group 2003 SHUTDOWN(P)