command notes - nicktehrany/notes GitHub Wiki

Here I just keep track of some common commands I run on VMs, making copy pasting quicker.

General Commands

sudo bpftrace ./trace.bt nvme0n2 4194304
sudo nvme zns report-zones /dev/nvme0n2 -d 7
sudo nvme zns reset-zone /dev/nvme0n2 -s  0x400000
cat /sys/kernel/debug/f2fs/status | grep -A30 "Multi-Stream INFO:"
sudo iostat /dev/nvme0n2 1 -x

sudo ${FIO_HOME}/fio --name=$(cat /proc/sys/kernel/random/uuid) --directory=/mnt/f2fs --size=4K --ioengine=sync --iodepth=1 --rw=write --bs=4K --runtime=30s --numjobs=1 --ioscheduler=mq-deadline --group_reporting --filename=file_1 --write_hint=short

dpkg --list | grep -E -i --color 'linux-image|linux-headers'

Page cache info

Writeback period

writeback thread wakeup period (is in value'th of a second) so 500 -> is every 500th of a second = 2ms

user@stosys:~/src/f2fs-zns-workloads/io-tracing$ cat /proc/sys/vm/dirty_writeback_centisecs
500

info on dirty stats

user@stosys:~/src/f2fs-zns-workloads/io-tracing$ cat /proc/vmstat | egrep "dirty|writeback"
nr_dirty 7
nr_writeback 0
nr_writeback_temp 0
nr_dirty_threshold 993396
nr_dirty_background_threshold 496091