Thanks, upgraded to 3.16.2 and xfsprogs 3.2.1. Let's see how it behaves with finobt. Greets, Stefan Am 07.09.2014 um 00:56 schrieb Dave Chinner: > On Sat, Sep 06, 2014 at 11:04:13AM -0400, Brian Foster wrote: >> On Sat, Sep 06, 2014 at 09:35:15AM +0200, Stefan Priebe wrote: >>> Hi Dave, >>> >>> Am 06.09.2014 01:05, schrieb Dave Chinner: >>>> On Fri, Sep 05, 2014 at 02:40:32PM +0200, Stefan Priebe - Profihost AG wrote: >>>>> >>>>> Am 05.09.2014 um 14:30 schrieb Brian Foster: >>>>>> On Fri, Sep 05, 2014 at 11:47:29AM +0200, Stefan Priebe - Profihost AG wrote: >>>>>>> Hi, >>>>>>> >>>>>>> i have a backup system running 20TB of storage having 350 million files. >>>>>>> This was working fine for month. >>>>>>> >>>>>>> But now the free space is so heavily fragmented that i only see the >>>>>>> kworker with 4x 100% CPU and write speed beeing very slow. 15TB of the >>>>>>> 20TB are in use. >>>> >>>> What does perf tell you about the CPU being burnt? (i.e run perf top >>>> for 10-20s while that CPU burn is happening and paste the top 10 CPU >>>> consuming functions). >>> >>> here we go: >>> 15,79% [kernel] [k] xfs_inobt_get_rec >>> 14,57% [kernel] [k] xfs_btree_get_rec >>> 10,37% [kernel] [k] xfs_btree_increment >>> 7,20% [kernel] [k] xfs_btree_get_block >>> 6,13% [kernel] [k] xfs_btree_rec_offset >>> 4,90% [kernel] [k] xfs_dialloc_ag >>> 3,53% [kernel] [k] xfs_btree_readahead >>> 2,87% [kernel] [k] xfs_btree_rec_addr >>> 2,80% [kernel] [k] _xfs_buf_find >>> 1,94% [kernel] [k] intel_idle >>> 1,49% [kernel] [k] _raw_spin_lock >>> 1,13% [kernel] [k] copy_pte_range >>> 1,10% [kernel] [k] unmap_single_vma >>> >> >> The top 6 or so items look related to inode allocation, so that probably >> confirms the primary bottleneck as searching around for free inodes out >> of the existing inode chunks, precisely what the finobt is intended to >> resolve. That was introduced in 3.16 kernels, so unfortunately it is not >> available in 3.10. > > *nod* > > Again, the only workaround for this on a non-finobt fs is to greatly > increase the number of AGs so there's less records in each btree to > search. > > Cheers, > > Dave. > _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
