● ubuntu提示“sudo: unable to resolve host volcano: No such file or directory”

修改/etc/hosts，在127.0.0.1 localhost后面添加主机名：volcano

127.0.0.1 localhost volcano

● 查询调度器：cat /sys/block/sda/queue/scheduler

p { margin-bottom: 0.1in; line-height: 120% }

改变调度器：echo ‘noop’ > /sys/block/sda/queue/scheduler

● Multi-queue

p { margin-bottom: 0.1in; line-height: 120% }

开启：

/etc/default/grub

GRUB_CMDLINE_LINUX="scsi_mod.use_blk_mq=1"

sudo update-grub

● ubuntu系统版本升级，先要 sudo apt-get update，然后，sudo update-manager -c -d