Hello, I''m testing btrfs on two 2TB drives with RAID1 on linux 3.9. So I have virtually a space of 2TB. I use iozone, bonnie++ and a lot of untaring linux kernel on fs to load it and see what''s happen. After some hours, I got ENOSPC and some daemon start crashing. I read wiki FAQ[1], and balance fix the issue (for few times). But running it again issue come back. The following is the output of untarnig linux kernel. # while true; do for i in *.tar.xz; do d=${i%.tar.xz}; echo $d; [[ -e "$d" ]] && rm -r "$d"; tar xf "$i"; done; done ... tar: linux-3.3/arch/sh: Cannot mkdir: No space left on device tar: linux-3.3/arch/sh/drivers/pci/fixups-sdk7786.c: Cannot open: No such file or directory tar: linux-3.3/arch/sh: Cannot mkdir: No space left on device tar: linux-3.3/arch/sh/drivers/pci/fixups-se7751.c: Cannot open: No such file or directory tar: linux-3.3/arch/sh: Cannot mkdir: No space left on device tar: linux-3.3/arch/sh/drivers/pci/fixups-sh03.c: Cannot open: No such file or directory # df Filesystem Size Used Avail Use% Mounted on /dev/sda2 3,7T 122G 3,6T 4% / # btrfs fi sh Label: ''achille.root'' uuid: 2ab5010c-e8fe-4b8a-a895-3e58552ed791 Total devices 2 FS bytes used 60.85GB devid 1 size 1.82TB used 65.02GB path /dev/sda2 devid 2 size 1.82TB used 65.01GB path /dev/sdb2 Btrfs v0.20-rc1 The first time ENOSPC happen on my FS, the previous command show each disk as full. Not like now (after the first run of "btrfs balance start / -dusage=5"). # btrfs fi df / Data, RAID1: total=61.00GB, used=59.99GB System, RAID1: total=8.00MB, used=16.00KB System: total=4.00MB, used=0.00 Metadata, RAID1: total=4.00GB, used=882.61MB Metadata: total=8.00MB, used=0.00 The following page[2] suggest me to enable enospc_debug. # mount -o remout,enospc_debug / # mount -t btrfs / /dev/sda2 on / type btrfs (rw,relatime,space_cache,enospc_debug) But I see nothing in dmesg. Where I can find the debug messages? So, I''m currently able to easily make the btrfs fs dirty without any way of seeing if there is a ENOPSC in some directory. [1] https://btrfs.wiki.kernel.org/index.php/FAQ#Help.21_Btrfs_claims_I.27m_out_of_space.2C_but_it_looks_like_I_should_have_lots_left.21 [2] https://btrfs.wiki.kernel.org/index.php/Mount_options -- Sébastien "Seblu" Luttringer https://www.seblu.net GPG: 0x2072D77A -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html