linux maximum number of open files and swap limit
The core linux 2.6+ will use a portion of the hard disk as a SWAP partition, used for process scheduling - the process is a running program - not the current process into a 'wait (standby)', or even 'sleep (sleep) 'Once you do, then tune into' activity (active) ', the process will lay sleeping SWAP partitions to sleep, the memory space to give out' activities' process.
If the memory is large enough, it should tell linux do not have to use too much SWAP partition, you can change the value of swappiness. swappiness = 0 indicates when the maximum physical memory and swap space is, swappiness = 100 indicates when an active use of swap area, and the timely data transfer memory to the swap space on the inside.
In ubuntu inside, swappiness default setting value is equal to 60.
Check swap usage
cat /proc/sys/vm/swappiness
Temporary modification
sudo sysctl vm.swappiness=10
or
echo 10 > /proc/sys/vm/swappiness But this is only temporary changes, after you reboot the system will restore the default 60, for the long-term stability, which goes further:
sudo gedit /etc/sysctl.conf
Add a line at the end of this document:
vm.swappiness=10
The maximum number of file viewing system allows open
cat /proc/sys/fs/file-max
Maximum number of files each user is allowed to view open
ulimit -a
The default is found open files (-n) 1024, problems arise here.
Modify the quantitative restrictions in the system file /etc/security/limits.conf, add the contents of the file:
* soft nofile 102400
* hard nofile 102400
Way to modify the configuration file will need to restart to take effect.