Package: src:linux Version: 4.3.3-5 Severity: normal I'm using BTRFS as root filesystem (with luks and DRBD 8.4.7 below), on a partition on a SSD.
Running the command $ fstrim -v -o 100000000 -l 100000000 / shows up in strace as open("/", O_RDONLY) = 4 fstat(4, {st_mode=S_IFDIR|0755, st_size=278, ...}) = 0 ioctl(4, FITRIM, {start=0x5f5e100, len=0x5f5e100, minlen=0}^C^C^C^CProcess 20160 detached <detached ...> but a "btrace" output shows this: 147,9 2 1125 0.505991030 20160 A D 2508256 + 1 <- (252,0) 2504160 147,9 2 1126 0.505991386 20160 Q D 2508256 + 1 [fstrim] 147,9 2 1127 0.506298337 20160 A D 411104 + 1 <- (252,0) 407008 147,9 2 1128 0.506298680 20160 Q D 411104 + 1 [fstrim] 147,9 2 1129 0.506554199 20160 A D 2508256 + 1 <- (252,0) 2504160 147,9 2 1130 0.506554518 20160 Q D 2508256 + 1 [fstrim] 147,9 2 1131 0.506806643 20160 A D 411104 + 1 <- (252,0) 407008 147,9 2 1132 0.506806977 20160 Q D 411104 + 1 [fstrim] 147,9 2 1133 0.507059795 20160 A D 2508256 + 1 <- (252,0) 2504160 147,9 2 1134 0.507060125 20160 Q D 2508256 + 1 [fstrim] 147,9 2 1135 0.507311777 20160 A D 411104 + 1 <- (252,0) 407008 147,9 2 1136 0.507312087 20160 Q D 411104 + 1 [fstrim] 147,9 2 1137 0.507563697 20160 A D 2508256 + 1 <- (252,0) 2504160 147,9 2 1138 0.507564052 20160 Q D 2508256 + 1 [fstrim] 147,9 2 1139 0.507815066 20160 A D 411104 + 1 <- (252,0) 407008 147,9 2 1140 0.507815413 20160 Q D 411104 + 1 [fstrim] 147,9 2 1141 0.508063192 20160 A D 2508256 + 1 <- (252,0) 2504160 147,9 2 1142 0.508063518 20160 Q D 2508256 + 1 [fstrim] 147,9 2 1143 0.508313576 20160 A D 411104 + 1 <- (252,0) 407008 147,9 2 1144 0.508313853 20160 Q D 411104 + 1 [fstrim] 147,9 2 1145 0.508549305 20160 A D 2508256 + 1 <- (252,0) 2504160 147,9 2 1146 0.508549637 20160 Q D 2508256 + 1 [fstrim] 147,9 2 1147 0.508813063 20160 A D 411104 + 1 <- (252,0) 407008 147,9 2 1148 0.508813372 20160 Q D 411104 + 1 [fstrim] Ie. "fstrim" makes the kernel's BTRFS FITRIM submit always the same two block numbers, seemingly in an endless loop. Perhaps related, running the command $ fstrim -v -o 0 -l 1000000000 / (ie. trim within the first 1 GB) returned /: 2 GiB (2159243264 bytes) trimmed and $ fstrim -v -o 0 -l 100000000 / (trim 100MB) said /: 991,6 MiB (1039757312 bytes) trimmed which is unexpected, too - the manual page states the units are bytes. Not sure how easy that is to reproduce - the root filesystem on that machine is 21 months old, and has seen quite a lot of dist-upgrades inbetween, so it might be heavily fragmented. -- Package-specific info: ** Version: Linux version 4.3.0-1-amd64 (debian-ker...@lists.debian.org) (gcc version 5.3.1 20160101 (Debian 5.3.1-5) ) #1 SMP Debian 4.3.3-5 (2016-01-04) ** Command line: BOOT_IMAGE=/vmlinuz-4.3.0-1-amd64 root=UUID=1bfc62e3-f883-42f0-a2aa-3c67ee6f563f ro quiet no_console_suspend=1 noresume cryptopts=source=/dev/drbd9,target=sda2_crypt,discard,rootdev cgroup_enable=memory swapaccount=1 ** Tainted: PWO (4609) * Proprietary module has been loaded. * Taint on warning. * Out-of-tree module has been loaded. -- System Information: Debian Release: stretch/sid APT prefers testing APT policy: (990, 'testing'), (500, 'unstable'), (500, 'stable'), (1, 'experimental') Architecture: amd64 (x86_64) Kernel: Linux 4.3.0-1-amd64 (SMP w/4 CPU cores) Locale: LANG=de_AT.UTF-8, LC_CTYPE=de_AT.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system) Versions of packages linux-image-4.3.0-1-amd64 depends on: ii debconf [debconf-2.0] 1.5.58 ii initramfs-tools [linux-initramfs-tool] 0.120 ii kmod 21-1 ii linux-base 4.0 Versions of packages linux-image-4.3.0-1-amd64 recommends: ii firmware-linux-free 3.4 ii irqbalance 1.1.0-2 Versions of packages linux-image-4.3.0-1-amd64 suggests: pn debian-kernel-handbook <none> ii extlinux 3:6.03+dfsg-11 ii grub-efi 2.02~beta2-33 pn linux-doc-4.3 <none> Versions of packages linux-image-4.3.0-1-amd64 is related to: pn firmware-atheros <none> pn firmware-bnx2 <none> ii firmware-bnx2x 20160110-1 ii firmware-brcm80211 20160110-1 pn firmware-intelwimax <none> pn firmware-ipw2x00 <none> pn firmware-ivtv <none> pn firmware-iwlwifi <none> pn firmware-libertas <none> ii firmware-linux 20160110-1 ii firmware-linux-nonfree 20160110-1 ii firmware-misc-nonfree [firmware-ralink] 20160110-1 pn firmware-myricom <none> pn firmware-netxen <none> pn firmware-qlogic <none> ii firmware-realtek 20160110-1 pn xen-hypervisor <none> -- debconf information: linux-image-4.3.0-1-amd64/postinst/mips-initrd-4.3.0-1-amd64: linux-image-4.3.0-1-amd64/postinst/depmod-error-initrd-4.3.0-1-amd64: false linux-image-4.3.0-1-amd64/prerm/removing-running-kernel-4.3.0-1-amd64: true