Context: I'm using prologue 0.6.6 on nim 2.0.0
Does anyone have any experience or tools for tracking down unclosed file descriptors? From what I understand unclosed FD's occur when "the remote peer has closed the connection (sent a FIN) but the local application hasn’t yet closed its end."
So I'm guessing this either from a db call, http request or websocket. But I've been going through my code and can't seem to find any instances of unclosed sockets, db calls or requests.
Are there any tools for further investigation?
root@ubuntu-s-1vcpu-1gb-nyc1-01:~# cfd
Process with PID 2625451 is using 369 open FDs, with 228 in CLOSE_WAIT.
root@ubuntu-s-1vcpu-1gb-nyc1-01:~# ls_fd
Listing file descriptors for process with PID 2625451:
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
app 2625451 root cwd DIR 252,1 4096 4027 /root/app
app 2625451 root rtd DIR 252,1 4096 2 /
app 2625451 root txt REG 252,1 9657128 78514 /root/app/app
app 2625451 root mem REG 252,1 485488 78080 /usr/lib/x86_64-linux-gnu/libpcre.so.3.13.3
...
app 2625451 root 4u IPv4 29618299 0t0 TCP localhost:7777 (LISTEN)
app 2625451 root 5u a_inode 0,14 0 12988 [eventpoll:6,90,199,231,232,236,256,264,301,304,322,334,338,346,348,351,352,357]
app 2625451 root 6u a_inode 0,14 0 12988 [timerfd]
app 2625451 root 7u IPv4 29618306 0t0 TCP localhost:7777->localhost:49948 (CLOSE_WAIT)
app 2625451 root 8u sock 0,8 0t0 29636936 protocol: TCP
app 2625451 root 9u sock 0,8 0t0 29618309 protocol: TCP
app 2625451 root 10u IPv4 29623847 0t0 TCP localhost:7777->localhost:34712 (CLOSE_WAIT)
app 2625451 root 11u IPv4 29618313 0t0 TCP localhost:7777->localhost:49964 (CLOSE_WAIT)
app 2625451 root 12u REG 252,1 176492544 36128 /root/app/ac.db
app 2625451 root 13u IPv4 29618316 0t0 TCP localhost:7777->localhost:49972 (CLOSE_WAIT)
app 2625451 root 14u sock 0,8 0t0 29745130 protocol: TCP
app 2625451 root 15u IPv4 29618323 0t0 TCP localhost:7777->localhost:49986 (CLOSE_WAIT)
app 2625451 root 16u IPv4 29796485 0t0 TCP localhost:7777->localhost:39192 (CLOSE_WAIT)
app 2625451 root 17u IPv4 29624945 0t0 TCP localhost:7777->localhost:54302 (CLOSE_WAIT)
app 2625451 root 18u sock 0,8 0t0 29619756 protocol: TCP
app 2625451 root 59u IPv4 29624838 0t0 TCP localhost:7777->localhost:34618 (CLOSE_WAIT)
app 2625451 root 60u IPv4 29643602 0t0 TCP localhost:7777->localhost:47998 (CLOSE_WAIT)
app 2625451 root 61u IPv4 29628119 0t0 TCP localhost:7777->localhost:45576 (CLOSE_WAIT)
app 2625451 root 62u IPv4 29629054 0t0 TCP localhost:7777->localhost:50752 (CLOSE_WAIT)
app 2625451 root 63u IPv4 29741820 0t0 TCP localhost:7777->localhost:46624 (CLOSE_WAIT)
app 2625451 root 64u IPv4 29630208 0t0 TCP localhost:7777->localhost:41636 (CLOSE_WAIT)
...