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Name	Size	Permission	Date
lib	[ DIR ]	drwxr-xr-x	2025-11-05 21:34
argdist_example.txt	22.49 KB	-rw-r--r--	2023-12-08 15:36
bashreadline_example.txt	882 B	-rw-r--r--	2023-12-08 15:36
bindsnoop_example.txt	4.42 KB	-rw-r--r--	2023-12-08 15:36
biolatency_example.txt	23.46 KB	-rw-r--r--	2023-12-08 15:36
biolatpcts_example.txt	2.97 KB	-rw-r--r--	2023-12-08 15:36
biopattern_example.txt	1.37 KB	-rw-r--r--	2023-12-08 15:36
biosnoop_example.txt	3.47 KB	-rw-r--r--	2023-12-08 15:36
biotop_example.txt	9.11 KB	-rw-r--r--	2023-12-08 15:36
bitesize_example.txt	4.98 KB	-rw-r--r--	2023-12-08 15:36
bpflist_example.txt	2.13 KB	-rw-r--r--	2023-12-08 15:36
btrfsdist_example.txt	9.32 KB	-rw-r--r--	2023-12-08 15:36
btrfsslower_example.txt	6.65 KB	-rw-r--r--	2023-12-08 15:36
cachestat_example.txt	3.92 KB	-rw-r--r--	2023-12-08 15:36
cachetop_example.txt	3.83 KB	-rw-r--r--	2023-12-08 15:36
capable_example.txt	6.5 KB	-rw-r--r--	2023-12-08 15:36
cobjnew_example.txt	2.97 KB	-rw-r--r--	2023-12-08 15:36
compactsnoop_example.txt	9.92 KB	-rw-r--r--	2023-12-08 15:36
cpudist_example.txt	16.48 KB	-rw-r--r--	2023-12-08 15:36
cpuunclaimed_example.txt	15.2 KB	-rw-r--r--	2023-12-08 15:36
criticalstat_example.txt	4.81 KB	-rw-r--r--	2023-12-08 15:36
cthreads_example.txt	2.08 KB	-rw-r--r--	2023-12-08 15:36
dbslower_example.txt	3.89 KB	-rw-r--r--	2023-12-08 15:36
dbstat_example.txt	6.5 KB	-rw-r--r--	2023-12-08 15:36
dcsnoop_example.txt	4.27 KB	-rw-r--r--	2023-12-08 15:36
dcstat_example.txt	3.26 KB	-rw-r--r--	2023-12-08 15:36
deadlock_example.txt	16.25 KB	-rw-r--r--	2023-12-08 15:36
dirtop_example.txt	4.98 KB	-rw-r--r--	2023-12-08 15:36
drsnoop_example.txt	5 KB	-rw-r--r--	2023-12-08 15:36
execsnoop_example.txt	6.64 KB	-rw-r--r--	2023-12-08 15:36
exitsnoop_example.txt	6.22 KB	-rw-r--r--	2023-12-08 15:36
ext4dist_example.txt	8.78 KB	-rw-r--r--	2023-12-08 15:36
ext4slower_example.txt	11.07 KB	-rw-r--r--	2023-12-08 15:36
filegone_example.txt	743 B	-rw-r--r--	2023-12-08 15:36
filelife_example.txt	2.04 KB	-rw-r--r--	2023-12-08 15:36
fileslower_example.txt	5.58 KB	-rw-r--r--	2023-12-08 15:36
filetop_example.txt	6.8 KB	-rw-r--r--	2023-12-08 15:36
funccount_example.txt	13.29 KB	-rw-r--r--	2023-12-08 15:36
funcinterval_example.txt	15.28 KB	-rw-r--r--	2023-12-08 15:36
funclatency_example.txt	20.98 KB	-rw-r--r--	2023-12-08 15:36
funcslower_example.txt	6.63 KB	-rw-r--r--	2023-12-08 15:36
gethostlatency_example.txt	1.29 KB	-rw-r--r--	2023-12-08 15:36
hardirqs_example.txt	37.05 KB	-rw-r--r--	2023-12-08 15:36
inject_example.txt	6.67 KB	-rw-r--r--	2023-12-08 15:36
javacalls_example.txt	3.91 KB	-rw-r--r--	2023-12-08 15:36
javaflow_example.txt	5.88 KB	-rw-r--r--	2023-12-08 15:36
javagc_example.txt	3.78 KB	-rw-r--r--	2023-12-08 15:36
javaobjnew_example.txt	2.97 KB	-rw-r--r--	2023-12-08 15:36
javastat_example.txt	2.98 KB	-rw-r--r--	2023-12-08 15:36
javathreads_example.txt	2.08 KB	-rw-r--r--	2023-12-08 15:36
killsnoop_example.txt	1.31 KB	-rw-r--r--	2023-12-08 15:36
klockstat_example.txt	8.34 KB	-rw-r--r--	2023-12-08 15:36
kvmexit_example.txt	11.63 KB	-rw-r--r--	2023-12-08 15:36
llcstat_example.txt	3.24 KB	-rw-r--r--	2023-12-08 15:36
mdflush_example.txt	1.74 KB	-rw-r--r--	2023-12-08 15:36
memleak_example.txt	10.02 KB	-rw-r--r--	2023-12-08 15:36
mountsnoop_example.txt	1.45 KB	-rw-r--r--	2023-12-08 15:36
mysqld_qslower_example.txt	2.3 KB	-rw-r--r--	2023-12-08 15:36
netqtop_example.txt	12.2 KB	-rw-r--r--	2023-12-08 15:36
nfsdist_example.txt	8.31 KB	-rw-r--r--	2023-12-08 15:36
nfsslower_example.txt	7.68 KB	-rw-r--r--	2023-12-08 15:36
nodegc_example.txt	3.78 KB	-rw-r--r--	2023-12-08 15:36
nodestat_example.txt	2.98 KB	-rw-r--r--	2023-12-08 15:36
offcputime_example.txt	19.2 KB	-rw-r--r--	2023-12-08 15:36
offwaketime_example.txt	37.36 KB	-rw-r--r--	2023-12-08 15:36
oomkill_example.txt	1.88 KB	-rw-r--r--	2023-12-08 15:36
opensnoop_example.txt	10.33 KB	-rw-r--r--	2023-12-08 15:36
perlcalls_example.txt	3.91 KB	-rw-r--r--	2023-12-08 15:36
perlflow_example.txt	5.88 KB	-rw-r--r--	2023-12-08 15:36
perlstat_example.txt	2.98 KB	-rw-r--r--	2023-12-08 15:36
phpcalls_example.txt	3.91 KB	-rw-r--r--	2023-12-08 15:36
phpflow_example.txt	5.88 KB	-rw-r--r--	2023-12-08 15:36
phpstat_example.txt	2.98 KB	-rw-r--r--	2023-12-08 15:36
pidpersec_example.txt	677 B	-rw-r--r--	2023-12-08 15:36
ppchcalls_example.txt	6.93 KB	-rw-r--r--	2023-12-08 15:36
profile_example.txt	31.08 KB	-rw-r--r--	2023-12-08 15:36
pythoncalls_example.txt	3.91 KB	-rw-r--r--	2023-12-08 15:36
pythonflow_example.txt	5.88 KB	-rw-r--r--	2023-12-08 15:36
pythongc_example.txt	3.78 KB	-rw-r--r--	2023-12-08 15:36
pythonstat_example.txt	2.98 KB	-rw-r--r--	2023-12-08 15:36
rdmaucma_example.txt	1.94 KB	-rw-r--r--	2023-12-08 15:36
readahead_example.txt	3.17 KB	-rw-r--r--	2023-12-08 15:36
reset-trace_example.txt	9.15 KB	-rw-r--r--	2023-12-08 15:36
rubycalls_example.txt	3.91 KB	-rw-r--r--	2023-12-08 15:36
rubyflow_example.txt	5.88 KB	-rw-r--r--	2023-12-08 15:36
rubygc_example.txt	3.78 KB	-rw-r--r--	2023-12-08 15:36
rubyobjnew_example.txt	2.97 KB	-rw-r--r--	2023-12-08 15:36
rubystat_example.txt	2.98 KB	-rw-r--r--	2023-12-08 15:36
runqlat_example.txt	31.3 KB	-rw-r--r--	2023-12-08 15:36
runqlen_example.txt	11.85 KB	-rw-r--r--	2023-12-08 15:36
runqslower_example.txt	2.13 KB	-rw-r--r--	2023-12-08 15:36
shmsnoop_example.txt	2.73 KB	-rw-r--r--	2023-12-08 15:36
slabratetop_example.txt	5.22 KB	-rw-r--r--	2023-12-08 15:36
sofdsnoop_example.txt	3.14 KB	-rw-r--r--	2023-12-08 15:36
softirqs_example.txt	11.02 KB	-rw-r--r--	2023-12-08 15:36
solisten_example.txt	2.3 KB	-rw-r--r--	2023-12-08 15:36
sslsniff_example.txt	6.74 KB	-rw-r--r--	2023-12-08 15:36
stackcount_example.txt	21.45 KB	-rw-r--r--	2023-12-08 15:36
statsnoop_example.txt	3.02 KB	-rw-r--r--	2023-12-08 15:36
swapin.txt	2.57 KB	-rw-r--r--	2023-12-08 15:36
swapin_example.txt	1.39 KB	-rw-r--r--	2023-12-08 15:36
syncsnoop_example.txt	387 B	-rw-r--r--	2023-12-08 15:36
syscount_example.txt	6.27 KB	-rw-r--r--	2023-12-08 15:36
tclcalls_example.txt	3.91 KB	-rw-r--r--	2023-12-08 15:36
tclflow_example.txt	5.88 KB	-rw-r--r--	2023-12-08 15:36
tclobjnew_example.txt	2.97 KB	-rw-r--r--	2023-12-08 15:36
tclstat_example.txt	2.98 KB	-rw-r--r--	2023-12-08 15:36
tcpaccept_example.txt	2.76 KB	-rw-r--r--	2023-12-08 15:36
tcpcong_example.txt	33.31 KB	-rw-r--r--	2023-12-08 15:36
tcpconnect_example.txt	6.27 KB	-rw-r--r--	2023-12-08 15:36
tcpconnlat_example.txt	2.55 KB	-rw-r--r--	2023-12-08 15:36
tcpdrop_example.txt	1.95 KB	-rw-r--r--	2023-12-08 15:36
tcplife_example.txt	6.83 KB	-rw-r--r--	2023-12-08 15:36
tcpretrans_example.txt	3.85 KB	-rw-r--r--	2023-12-08 15:36
tcprtt_example.txt	9.83 KB	-rw-r--r--	2023-12-08 15:36
tcpstates_example.txt	2.84 KB	-rw-r--r--	2023-12-08 15:36
tcpsubnet_example.txt	5.37 KB	-rw-r--r--	2023-12-08 15:36
tcpsynbl_example.txt	1.15 KB	-rw-r--r--	2023-12-08 15:36
tcptop_example.txt	5.75 KB	-rw-r--r--	2023-12-08 15:36
tcptracer_example.txt	1.98 KB	-rw-r--r--	2023-12-08 15:36
threadsnoop_example.txt	1.07 KB	-rw-r--r--	2023-12-08 15:36
tplist_example.txt	4.4 KB	-rw-r--r--	2023-12-08 15:36
trace_example.txt	21.62 KB	-rw-r--r--	2023-12-08 15:36
ttysnoop_example.txt	3.24 KB	-rw-r--r--	2023-12-08 15:36
vfscount_example.txt	2.17 KB	-rw-r--r--	2023-12-08 15:36
vfsstat_example.txt	1.66 KB	-rw-r--r--	2023-12-08 15:36
virtiostat_example.txt	2.62 KB	-rw-r--r--	2023-12-08 15:36
wakeuptime_example.txt	33.25 KB	-rw-r--r--	2023-12-08 15:36
xfsdist_example.txt	6.77 KB	-rw-r--r--	2023-12-08 15:36
xfsslower_example.txt	6.91 KB	-rw-r--r--	2023-12-08 15:36
zfsdist_example.txt	9.52 KB	-rw-r--r--	2023-12-08 15:36
zfsslower_example.txt	7.37 KB	-rw-r--r--	2023-12-08 15:36

Rename

Demonstrations of tcpdrop, the Linux BPF/bcc version.

tcpdrop prints details of TCP packets or segments that were dropped by the
kernel, including the kernel stack trace that led to the drop:

# ./tcpdrop.py
TIME     PID    IP SADDR:SPORT          > DADDR:DPORT          STATE (FLAGS)
20:49:06 0      4  10.32.119.56:443     > 10.66.65.252:22912   CLOSE (ACK)
	tcp_drop+0x1
	tcp_v4_do_rcv+0x135
	tcp_v4_rcv+0x9c7
	ip_local_deliver_finish+0x62
	ip_local_deliver+0x6f
	ip_rcv_finish+0x129
	ip_rcv+0x28f
	__netif_receive_skb_core+0x432
	__netif_receive_skb+0x18
	netif_receive_skb_internal+0x37
	napi_gro_receive+0xc5
	ena_clean_rx_irq+0x3c3
	ena_io_poll+0x33f
	net_rx_action+0x140
	__softirqentry_text_start+0xdf
	irq_exit+0xb6
	do_IRQ+0x82
	ret_from_intr+0x0
	native_safe_halt+0x6
	default_idle+0x20
	arch_cpu_idle+0x15
	default_idle_call+0x23
	do_idle+0x17f
	cpu_startup_entry+0x73
	rest_init+0xae
	start_kernel+0x4dc
	x86_64_start_reservations+0x24
	x86_64_start_kernel+0x74
	secondary_startup_64+0xa5

20:49:50 12431  4  127.0.0.1:8198       > 127.0.0.1:48280      CLOSE (RST|ACK)
	tcp_drop+0x1
	tcp_v4_do_rcv+0x135
	__release_sock+0x88
	release_sock+0x30
	inet_stream_connect+0x47
	SYSC_connect+0x9e
	sys_connect+0xe
	do_syscall_64+0x73
	entry_SYSCALL_64_after_hwframe+0x3d

[...]

The last two columns show the state of the TCP session, and the TCP flags.
These two examples show packets arriving for a session in the closed state,
that were dropped by the kernel.

This tool is useful for debugging high rates of drops, which can cause the
remote end to do timer-based retransmits, hurting performance.

USAGE:

# ./tcpdrop.py -h
usage: tcpdrop.py [-4 | -6] [-h]

Trace TCP drops by the kernel

optional arguments:
  -4, --ipv4  trace IPv4 family only
  -6, --ipv6  trace IPv6 family only
  -h, --help  show this help message and exit

examples:
    ./tcpdrop           # trace kernel TCP drops
    ./tcpdrop -4        # trace IPv4 family only
    ./tcpdrop -6        # trace IPv6 family only