파일 버퍼 관련 커널 정보 수집

출처 : http://www.cyrius.com/debian/nslu2/linux-on-flash.html


centiseconds는 1/100

• /proc/sys/vm/laptop_mode: How many seconds after a read should a writeout of changed files start (this is based on the assumption that a read will cause an otherwise spun down disk to spin up again).
• /proc/sys/vm/dirty_writeback_centisecs: How often the kernel should check if there is "dirty" (changed) data to write out to disk (in centiseconds).
• /proc/sys/vm/dirty_expire_centisecs: How old "dirty" data should be before the kernel considers it old enough to be written to disk. It is in general a good idea to set this to the same value as dirty_writeback_centisecs above.
• /proc/sys/vm/dirty_ratio: The maximum amount of memory (in percent) to be used to store dirty data before the process that generates the data will be forced to write it out. Setting this to a high value should not be a problem as writeouts will also occur if the system is low on memory.
• /proc/sys/vm/dirty_background_ratio: The lower amount of memory (in percent) where a writeout of dirty data to disk is allowed to stop. This should be quite a bit lower than the above dirty_ratio to allow the kernel to write out chunks of dirty data in one go.