FM / examples

/usr/share/doc/bpftrace/examples

Name	Size	Mode	Actions
bashreadline_example.txt	722	0644	edit dl rm
biolatency_example.txt	1790	0644	edit dl rm
biosnoop_example.txt	2056	0644	edit dl rm
biostacks_example.txt	1914	0644	edit dl rm
bitesize_example.txt	3003	0644	edit dl rm
capable_example.txt	2659	0644	edit dl rm
cpuwalk_example.txt	4919	0644	edit dl rm
dcsnoop_example.txt	4612	0644	edit dl rm
execsnoop_example.txt	1535	0644	edit dl rm
gethostlatency_example.txt	923	0644	edit dl rm
killsnoop_example.txt	846	0644	edit dl rm
loads_example.txt	864	0644	edit dl rm
mdflush_example.txt	1866	0644	edit dl rm
naptime_example.txt	844	0644	edit dl rm
oomkill_example.txt	1668	0644	edit dl rm
opensnoop_example.txt	2528	0644	edit dl rm
pidpersec_example.txt	1504	0644	edit dl rm
runqlat_example.txt	8632	0644	edit dl rm
runqlen_example.txt	980	0644	edit dl rm
setuids_example.txt	2441	0644	edit dl rm
ssllatency_example.txt	4510	0644	edit dl rm
sslsnoop_example.txt	1916	0644	edit dl rm
statsnoop_example.txt	2738	0644	edit dl rm
swapin_example.txt	549	0644	edit dl rm
syncsnoop_example.txt	541	0644	edit dl rm
syscount_example.txt	1144	0644	edit dl rm
tcpaccept_example.txt	1350	0644	edit dl rm
tcpconnect_example.txt	1085	0644	edit dl rm
tcpdrop_example.txt	1256	0644	edit dl rm
tcplife_example.txt	1597	0644	edit dl rm
tcpretrans_example.txt	1153	0644	edit dl rm
tcpsynbl_example.txt	940	0644	edit dl rm
threadsnoop_example.txt	1182	0644	edit dl rm
undump_example.txt	680	0644	edit dl rm
vfscount_example.txt	1199	0644	edit dl rm
vfsstat_example.txt	929	0644	edit dl rm
writeback_example.txt	1962	0644	edit dl rm
xfsdist_example.txt	3419	0644	edit dl rm

Edit: /usr/share/doc/bpftrace/examples/biostacks_example.txt (1914B)

Demonstrations of biostacks, the Linux BCC/eBPF version.

This tool shows block I/O latency as a histogram, with the kernel stack trace
that initiated the I/O. This can help explain disk I/O that is not directly
requested by applications (eg, metadata reads on writes, resilvering, etc).
For example:

# ./biostacks.bt 
Attaching 5 probes...
Tracing block I/O with init stacks. Hit Ctrl-C to end.
^C

@usecs[
    blk_account_io_start+1
    blk_mq_make_request+1102
    generic_make_request+292
    submit_bio+115
    _xfs_buf_ioapply+798
    xfs_buf_submit+101
    xlog_bdstrat+43
    xlog_sync+705
    xlog_state_release_iclog+108
    _xfs_log_force+542
    xfs_log_force+44
    xfsaild+428
    kthread+289
    ret_from_fork+53
]: 
[64K, 128K)            1 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|

[...]

@usecs[
    blk_account_io_start+1
    blk_mq_make_request+707
    generic_make_request+292
    submit_bio+115
    xfs_add_to_ioend+455
    xfs_do_writepage+758
    write_cache_pages+524
    xfs_vm_writepages+190
    do_writepages+75
    __writeback_single_inode+69
    writeback_sb_inodes+481
    __writeback_inodes_wb+103
    wb_writeback+625
    wb_workfn+384
    process_one_work+478
    worker_thread+50
    kthread+289
    ret_from_fork+53
]: 
[8K, 16K)            560 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|
[16K, 32K)           218 |@@@@@@@@@@@@@@@@@@@@                                |
[32K, 64K)            26 |@@                                                  |
[64K, 128K)            2 |                                                    |
[128K, 256K)          53 |@@@@                                                |
[256K, 512K)          60 |@@@@@                                               |

This output shows the most frequent stack was XFS writeback, with latencies
between 8 and 512 microseconds. The other stack included here shows an XFS
log sync.

Demonstrations of biostacks, the Linux BCC/eBPF version. This tool shows block I/O latency as a histogram, with the kernel stack trace that initiated the I/O. This can help explain disk I/O that is not directly requested by applications (eg, metadata reads on writes, resilvering, etc). For example: # ./biostacks.bt Attaching 5 probes... Tracing block I/O with init stacks. Hit Ctrl-C to end. ^C @usecs[ blk_account_io_start+1 blk_mq_make_request+1102 generic_make_request+292 submit_bio+115 _xfs_buf_ioapply+798 xfs_buf_submit+101 xlog_bdstrat+43 xlog_sync+705 xlog_state_release_iclog+108 _xfs_log_force+542 xfs_log_force+44 xfsaild+428 kthread+289 ret_from_fork+53 ]: [64K, 128K) 1 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [...] @usecs[ blk_account_io_start+1 blk_mq_make_request+707 generic_make_request+292 submit_bio+115 xfs_add_to_ioend+455 xfs_do_writepage+758 write_cache_pages+524 xfs_vm_writepages+190 do_writepages+75 __writeback_single_inode+69 writeback_sb_inodes+481 __writeback_inodes_wb+103 wb_writeback+625 wb_workfn+384 process_one_work+478 worker_thread+50 kthread+289 ret_from_fork+53 ]: [8K, 16K) 560 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [16K, 32K) 218 |@@@@@@@@@@@@@@@@@@@@ | [32K, 64K) 26 |@@ | [64K, 128K) 2 | | [128K, 256K) 53 |@@@@ | [256K, 512K) 60 |@@@@@ | This output shows the most frequent stack was XFS writeback, with latencies between 8 and 512 microseconds. The other stack included here shows an XFS log sync.