File Limits

Default number of file descriptors is 4096
This is not enough for many applications

echo 128000 > /proc/sys/fs/inode-max
echo 64000 > /proc/sys/fs/file-max
ulimit -n 64000

cat  /proc/sys/fs/file-nr
To see how many file descriptors are currently in use

Theoretical limit of ~1,000,000
Each file takes a chunk of ram
Some apps may get slower. If they do, the app sucks.