From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Sandeen Subject: Re: very slow file deletion on an SSD Date: Sat, 26 May 2012 21:43:22 -0500 Message-ID: <4FC194CA.9070100@sandeen.net> References: <4FBF60D1.80104@gmail.com> <20120526231838.GR25351@dastard> <4FC16683.9060800@gmail.com> <20120527000701.GS25351@dastard> <4FC18845.6030301@gmail.com> <4FC19408.5020502@sandeen.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4FC19408.5020502@sandeen.net> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Joe Landman Cc: linux-raid , xfs@oss.sgi.com List-Id: linux-raid.ids On 5/26/12 9:40 PM, Eric Sandeen wrote: > On 5/26/12 8:49 PM, Joe Landman wrote: >> On 05/26/2012 08:07 PM, Dave Chinner wrote: >>> On Sat, May 26, 2012 at 07:25:55PM -0400, Joe Landman wrote: >>>> [root@siFlash test]# ls -alF | wc -l >>>> 59 >>>> [root@siFlash test]# /usr/bin/time rm -f * >>>> ^C0.00user 8.46system 0:09.55elapsed 88%CPU (0avgtext+0avgdata >>>> 2384maxresident)k >>>> 25352inputs+0outputs (0major+179minor)pagefaults 0swaps >>> >>> It's burning an awful lot of CPU time during this remove. >>> >>>> [root@siFlash test]# ls -alF | wc -l >>>> 48 >>> >>> So, 48 files were removed, it was basically CPU bound and one took >>> 2.6 seconds. >>> >>> So, how big are the files, and does the one that took 2.6s have tens >>> of thousands of extents ('xfs_bmap -vp *' will dump the extent maps >>> for all the files)? >> >> Getting some sort of out of memory error with bmap >> >> [root@siFlash test]# ls -alF >> total 50466476 >> drwxr-xr-x 2 root root 4096 May 26 21:40 ./ >> drwxr-xr-x 3 root root 17 May 26 19:32 ../ >> -rw------- 1 root root 1073741824 May 26 19:36 2.r.49.0 > ... > > > >> [root@siFlash test]# ls -alF > x >> >> [root@siFlash test]# xfs_bmap -vp x >> x: >> EXT: FILE-OFFSET BLOCK-RANGE AG AG-OFFSET TOTAL FLAGS >> 0: [0..7]: 212681896..212681903 2 (7555752..7555759) 8 01111 >> >> [root@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. Ah. f074211f xfs: fallback to vmalloc for large buffers in xfs_getbmap fixed it in 3.4 -Eric _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs