very slow file deletion on an SSD

[Stefan Ring]

>> [root at siFlash test]# xfs_bmap -vp 2.r.96.0
>> xfs_bmap: xfsctl(XFS_IOC_GETBMAPX) iflags=0x4 ["2.r.96.0"]: Cannot allocate memory
>
> Try filefrag -v maybe, if your e2fsprogs is new enough.
>
> Trying to remember, ENOMEM in bmap rings a bell... but this is possibly indicative of an extremely fragmented file.

True, I've had it happen with extremely fragmented files.

I've started playing around with discard myself only recently, but so
far I like the approach of using fstrim a lot better than the discard
option: http://xfs.org/index.php/FITRIM/discard