On May 26, 6:59pm, Graeme Tait wrote: } Subject: File system gets too fragmented ???
} The filesystem is built with 4096 byte blocks, 512 byte fragments, and } 2048 bytes/inode, and is mounted 'async noatime'. } } It contains about 900,000 files, most of which are small, occupying } around 2-5 fragments. The small files are updated monthly from a tar } archive generated offline. In the course of updates, some files may grow } or shrink by a fragment or so, and some new files are created, and } periodically old files are deleted. If a file shrinks by one fragment, it'll most likely leave a one fragment gap in the block that can't be reused by another (new) file, since the the minimum file size is two fragments. You could easily get a 12.5% wasteage just from that. It might help somewhat if a file that grows by a fragment can allocate the free fragment immediately preceeding it instead of being relocated to a fresh block. I don't know if FFS does this or not. Forcing space optimization full time might help, but this is a pretty nasty allocation pattern ... To Unsubscribe: send mail to majord...@freebsd.org with "unsubscribe freebsd-hackers" in the body of the message
