Re: Discard support (was Re: [PATCH] swap: send callback when swap slot is freed)
From: Mark Lord <hidden>
Date: 2009-08-15 13:12:18
Also in:
linux-mm, linux-raid, linux-scsi, lkml
From: Mark Lord <hidden>
Date: 2009-08-15 13:12:18
Also in:
linux-mm, linux-raid, linux-scsi, lkml
Greg Freemyer wrote:
What filesystems does your script support? Running a tool like this in the middle of the night makes a lot of since to me even from the perspective of many / most enterprise users.
.. It is designed to work on any *mounted* filesystem that supports the fallocate() system call. It uses fallocate() to reserve the free space in a temporary file without any I/O, and then FIEMAP/FIBMAP to get the block lists from the fallocated file, and then SGIO/ATA_16:TRIM to discard the space, before deleting the fallocated file. Tested by me on ext4 and xfs. btrfs has a bug that prevents the fallocate from succeeding at present, but CM say's they're trying to fix that. It will also work on *unmounted" ext2/ext3/ext4 filesystems, using dumpe2fs to get the free lists, and on xfs using xfs_db there. HFS(+) support is coming as well. Not currently compatible with LVM 1/2, or with some distros that use imaginary device names in /proc/mounts --> I'm working on those issues.
ps: I tried to pull wiper.sh straight from sourceforge, but I'm getting some crazy page asking all sorts of questions and not letting me bypass it. I hope sourceforge is broken. The other option is they meant to do this. :(
.. That's weird. It should just be a simple click/download, though you will need to also upgrade hdparm to the latest version. Cheers -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>