nofiles in ulimit

Hi all,

What are the nofiles in ulimit for? How can these affect the server performance? What are the desired values for this? below is the result of ulimit -a on the server.

time(seconds)        unlimited
file(blocks)         unlimited
data(kbytes)         unlimited
stack(kbytes)        4194304
memory(kbytes)       unlimited
coredump(blocks)     unlimited
nofiles(descriptors) unlimited
threads(per process) unlimited
processes(per user)  unlimited

Is it okay that almost all (except stack) is set to unlimited?

nofiles is the max number of concurrently open files for a process. Usually unlimited is okay. On servers with huge numbers of concurrent users it might not be a good idea.