void global_cached_io::process_all_requests()
{
// We first process the completed requests from the disk.
// It will add completed user requests and pending requests to queues
// for further processing.
while (!completed_disk_queue.is_empty()) {
int num = completed_disk_queue.get_num_entries();
stack_array<io_request> reqs(num);
int ret = completed_disk_queue.fetch(reqs.data(), num);
process_disk_completed_requests(reqs.data(), ret);
}
// Process the requests that are pending on the pages.
// It may add completed user requests to queues for further processing.
if (!pending_requests.is_empty())
handle_pending_requests();
// Process buffered user requests.
// It may add completed user requests to queues for further processing.
process_user_reqs();
std::vector<io_request> requests;
// Process the completed requests served in the cache directly.
process_cached_reqs(requests);
// Process completed user requests.
process_completed_requests(requests);
// Process requests issued in the user compute.
// We try to gather all requests so we can merge them. However, we only
// have the local collection of the requests. We still need to rely on
// the OS's elevator algorithm to merge the requests from different
// global_cached_io.
access(requests.data(), requests.size(), NULL);
// Processing the pending requests on the pages might issue
// more I/O requests.
flush_requests();
}
int serve(struct server *srv)
{
const static int CONTROL_PFD = 0;
struct pollfd pfd[1];
memset(&pfd, 0, sizeof(pfd));
pfd[CONTROL_PFD].fd = srv->ctl_fd;
pfd[CONTROL_PFD].events = POLLIN;
while (! srv->bquit) {
int n = poll(pfd, sizeof(pfd)/sizeof(struct pollfd), -1);
if (n < 0) {
fprintf(stderr, "poll error\n");
return -1;
}
else if (n == 0) {
}
else {
process_conns();
process_client_reqs();
process_user_reqs(&pfd[CONTROL_PFD], &pfd[CONTROL_PFD].fd);
}
}
}
