current.md

Sampling 33 processes which have been stuck for some time, they all report the same in eu-stack:

# eu-stack -p 4069 -s
PID 4069 - process
TID 4069:
#0  0x00007f9c14b19447 __select
    ../sysdeps/unix/sysv/linux/select.c:41
#1  0x00005607fbdd4cd7 client_loop
#2  0x00005607fbdc928a main
#3  0x00007f9c14a50b8e __libc_start_main
    ../csu/libc-start.c:308
#4  0x00005607fbdcad9a _start

# strace -p 4069
strace: Process 4069 attached
select(7, [3 4], [], NULL, {tv_sec=57, tv_usec=386199}) = 0 (Timeout)
clock_gettime(CLOCK_BOOTTIME, {tv_sec=1379345, tv_nsec=724140026}) = 0
getpid()                                = 4069
clock_gettime(CLOCK_BOOTTIME, {tv_sec=1379345, tv_nsec=724790292}) = 0
clock_gettime(CLOCK_BOOTTIME, {tv_sec=1379345, tv_nsec=724959365}) = 0
clock_gettime(CLOCK_BOOTTIME, {tv_sec=1379345, tv_nsec=725034521}) = 0
select(7, [3 4], [3], NULL, {tv_sec=120, tv_usec=0}) = 1 (out [3], left {tv_sec=119, tv_usec=999993})
clock_gettime(CLOCK_BOOTTIME, {tv_sec=1379345, tv_nsec=725240041}) = 0
write(3, "\312z\371F\267\230\215\216\227X\t\5\257NU\266\27\362(!\254\25>(\375\377]V\342\262\367h"..., 52) = 52
clock_gettime(CLOCK_BOOTTIME, {tv_sec=1379345, tv_nsec=725437253}) = 0
clock_gettime(CLOCK_BOOTTIME, {tv_sec=1379345, tv_nsec=725507223}) = 0
select(7, [3 4], [], NULL, {tv_sec=120, tv_usec=0}) = 1 (in [3], left {tv_sec=119, tv_usec=988837})
clock_gettime(CLOCK_BOOTTIME, {tv_sec=1379345, tv_nsec=737160918}) = 0
read(3, "\\\354(w\236\343B\375\36B\356\367\243^\347\3537\326i\235R#\336\275\271)\254\307", 8192) = 28
clock_gettime(CLOCK_BOOTTIME, {tv_sec=1379345, tv_nsec=737804655}) = 0
clock_gettime(CLOCK_BOOTTIME, {tv_sec=1379345, tv_nsec=737917147}) = 0
select(7, [3 4], [], NULL, {tv_sec=120, tv_usec=0}

(gdb) bt
#0  0x00007f9c14b19447 in __GI___select (nfds=7, readfds=0x5607fd070b70, writefds=0x5607fd070af0, exceptfds=0x0, timeout=0x7ffdbdd64e60) at ../sysdeps/unix/sysv/linux/select.c:41
#1  0x00005607fbdd4cd7 in client_loop ()
#2  0x00005607fbdc928a in main ()