OSB, number of files open

We run an environment with Whole Server Migration.

An important point is to make sure that we have enough resources (file handles) on a machine to be able to run 2 Managed Server - in case we migrate one.

This is how you discover how many files are used by the user "soa":

/usr/sbin/lsof -u soa | wc -l

It turned out that a single server running the Admin and 4 Managed Servers required some 9000 files. An important load was represented by the MANY Datasources we need to deploy.

This command:
ulimit -a

will tell you the hard limit imposed by the Linux Kernel:

ulimit -a
core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 132607
max locked memory (kbytes, -l) 32
max memory size (kbytes, -m) unlimited
open files (-n) 8192
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 10240
cpu time (seconds, -t) unlimited
max user processes (-u) 132607
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited


apparently the limit is flexible, even with a limit of 8192 we were able to open 9050 files...