#
# Tell the kernel to use up to 10% of the RAM as cache for writes
# On systems with lot of ram can be lowered even more.
# Write cache is not free, and overuse of RAM for it
# can cause low memory conditions simultaneously with IO clog.
#

# The infamous issues with writing to USB Flash drives partially caused by
# write cache being too big.
vm.dirty_ratio=10

# Instruct kernel to use up to 5% of RAM before slowing down the process that's writing
# Works in congestion with previous setting. And serving same purpose: protect system responsiveness.
vm.dirty_background_ratio=5



# ******** Options below is for information purposes and possible future enablement. **********


# The value controls the tendency of the kernel to reclaim the memory which is used for caching of directory and inode objects (VFS cache).
# Lowering it from the default value of 100 makes the kernel less inclined to reclaim VFS cache (do not set it to 0, this may produce out-of-memory conditions)
#vm.vfs_cache_pressure=50

# Contains, as a bytes of total available memory that contains free pages and reclaimable
# pages, the number of pages at which a process which is generating disk writes will itself start
# writing out dirty data.
#vm.dirty_bytes = 268435456

# Contains, as a bytes of total available memory that contains free pages and reclaimable
# pages, the number of pages at which the background kernel flusher threads will start writing out
# dirty data.
#vm.dirty_background_bytes = 134217728

# This tunable is used to define when dirty data is old enough to be eligible for writeout by the
# kernel flusher threads.  It is expressed in 100'ths of a second.  Data which has been dirty
# in-memory for longer than this interval will be written out next time a flusher thread wakes up
# (Default is 3000).
#vm.dirty_expire_centisecs = 3000

# The kernel flusher threads will periodically wake up and write old data out to disk.  This
# tunable expresses the interval between those wake-ups, in 100'ths of a second (Default is 500).
# vm.dirty_writeback_centisecs = 1500

# Increase writeback interval  for xfs
# fs.xfs.xfssyncd_centisecs = 10000

# Set the maximum watches on files
#fs.inotify.max_user_watches = 524288

# Set size of file handles and inode cache
#fs.file-max = 2097152