# taskset -c 0 btrfs send /mnt/first/subvol.ro/ | btrfs receive /mnt/int/
Attaching top and perf top while this send receive happens. The use of
taskset -c 0 doesn't seem to affect the results.
Chris Murphy
Samples: 51K of event 'cycles:pp', Event count (approx.): 13435020269
Overhead Shared Object Symbol
18.04% btrfs [.] __crc32c_le
8.50% [kernel] [k] _aesni_dec4
6.75% [kernel] [k] __radix_tree_lookup
5.00% [kernel] [k] copy_user_enhanced_fast_string
2.41% [kernel] [k] memcpy_erms
1.89% [kernel] [k] send_extent_data
1.77% [kernel] [k] aesni_xts_crypt8
0.99% [kernel] [k] memset_erms
0.94% [kernel] [k] update_blocked_averages
0.89% [kernel] [k] __wake_up_bit
0.82% [kernel] [k] crypt_convert
0.77% [kernel] [k] get_page_from_freelist
0.70% [kernel] [k] __list_del_entry
0.47% [kernel] [k] _aesni_enc1
0.46% [kernel] [k] glue_xts_crypt_128bit
0.41% [kernel] [k] __do_page_cache_readahead
0.39% [kernel] [k] radix_tree_lookup
0.36% [kernel] [k] _raw_spin_lock
0.36% [kernel] [k] cfb_imageblit
0.35% perf [.] dso__find_symbol
0.35% [kernel] [k] crc_96
0.33% [kernel] [k] crc_48
0.33% [kernel] [k] crc_128
0.31% [kernel] [k] crc_42
0.31% [kernel] [k] crc_32
0.31% [kernel] [k] crc_80
0.31% [kernel] [k] __schedule
0.31% [kernel] [k] bad_range
0.30% [kernel] [k] __check_object_size
0.30% [kernel] [k] crc_112
0.30% [kernel] [k] _raw_spin_lock_irqsave
0.30% [kernel] [k] free_hot_cold_page
0.29% [kernel] [k] crc_64
0.29% [kernel] [k] crc_16
0.28% [kernel] [k] module_get_kallsym
0.28% [kernel] [k] generic_bin_search.constprop.37
0.27% [kernel] [k] pipe_write
0.27% libc-2.24.so [.] vfprintf
0.27% libc-2.24.so [.] __strcmp_sse2_unaligned
0.27% [kernel] [k] free_pcppages_bulk
0.26% [kernel] [k] blkcipher_walk_next
0.26% [kernel] [k] __btrfs_map_block
0.26% [kernel] [k] __alloc_pages_nodemask
0.26% [kernel] [k] page_cache_prev_hole
0.26% [kernel] [k] unlock_page
0.25% [kernel] [k] __lookup_extent_mapping
0.25% [kernel] [k] kmem_cache_alloc
no symbols passed the given filter.
top - 15:12:02 up 8 min, 2 users, load average: 0.51, 0.22, 0.12
Tasks: 208 total, 3 running, 205 sleeping, 0 stopped, 0 zombie
%Cpu(s): 6.8 us, 19.9 sy, 0.0 ni, 57.3 id, 14.2 wa, 0.9 hi, 0.9 si, 0.0 st
KiB Mem : 3965204 total, 2756344 free, 166196 used, 1042664 buff/cache
KiB Swap: 8388604 total, 8388604 free, 0 used. 3528528 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1367 root 20 0 15928 1180 1040 R 38.6 0.0 0:02.51 btrfs
1366 root 20 0 24124 1160 1016 R 27.1 0.0 0:01.67 btrfs
1249 root 20 0 0 0 0 S 9.2 0.0 0:00.70 kworker/u8:0
123 root 20 0 0 0 0 S 7.9 0.0 0:00.81 kworker/u8:3
1319 root 20 0 0 0 0 S 5.9 0.0 0:00.20 kworker/u8:5
57 root 20 0 0 0 0 S 5.0 0.0 0:00.85 kworker/u8:1
1370 root 20 0 0 0 0 S 5.0 0.0 0:00.15 kworker/u8:6
113 root 20 0 0 0 0 S 4.3 0.0 0:00.43 kworker/u8:2
153 root 20 0 0 0 0 S 3.3 0.0 0:00.56 kworker/u8:4
815 root 20 0 139696 2964 2708 S 0.7 0.1 0:03.94 agetty
1369 chris 20 0 156664 4236 3720 R 0.7 0.1 0:00.07 top
7 root 20 0 0 0 0 S 0.3 0.0 0:00.29 rcu_sched
9 root 20 0 0 0 0 S 0.3 0.0 0:00.15 rcuos/0
21 root 20 0 0 0 0 S 0.3 0.0 0:00.09 rcuos/1
787 root 20 0 467188 14556 11664 S 0.3 0.4 0:02.32
NetworkManager
1 root 20 0 149296 10724 7692 S 0.0 0.3 0:03.19 systemd
2 root 20 0 0 0 0 S 0.0 0.0 0:00.02 kthreadd
3 root 20 0 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/0
5 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/0:0H
