Ming Lei - 30.01.18, 02:24: > > > SCSI_MQ is enabled on V3.17 firstly, but disabled at default. In > > > V4.13-rc1, it is enabled at default, but later the patch is reverted > > > in V4.13-rc7, and becomes disabled at default too. > > > > > > Now both the original reported PM issue(actually SCSI quiesce) and > > > the sequential IO performance issue have been addressed. > > > > Is the blocker bug just not closed because no-one thought to do it: > > > > https://bugzilla.kernel.org/show_bug.cgi?id=178381 > > > > (we have confirmed that this issue is now fixed with the original > > reporter?) > > From a developer view, this issue is fixed by the following commit: > 3a0a52997(block, scsi: Make SCSI quiesce and resume work reliably), > and it is verified by kernel list reporter. I never seen any suspend / hibernate related issues with blk-mq + bfq since then. Using heavily utilized BTRFS dual SSD RAID 1. % egrep "MQ|BFQ" /boot/config-4.15.0-tp520-btrfstrim+ CONFIG_POSIX_MQUEUE=y CONFIG_POSIX_MQUEUE_SYSCTL=y CONFIG_BLK_WBT_MQ=y CONFIG_BLK_MQ_PCI=y CONFIG_BLK_MQ_VIRTIO=y CONFIG_MQ_IOSCHED_DEADLINE=m CONFIG_MQ_IOSCHED_KYBER=m CONFIG_IOSCHED_BFQ=m CONFIG_BFQ_GROUP_IOSCHED=y CONFIG_NET_SCH_MQPRIO=m # CONFIG_SCSI_MQ_DEFAULT is not set # CONFIG_DM_MQ_DEFAULT is not set CONFIG_DM_CACHE_SMQ=m % cat /proc/cmdline BOOT_IMAGE=/vmlinuz-4.15.0-tp520-btrfstrim+ root=UUID=[…] ro rootflags=subvol=debian resume=/dev/mapper/sata-swap init=/bin/systemd thinkpad_acpi.fan_control=1 systemd.restore_state=0 scsi_mod.use_blk_mq=1 % cat /sys/block/sda/queue/scheduler [bfq] none Thanks, -- Martin
