We definitely need more info. If you could attach your fpm config. Ideally please set process.dumpable and then you should be able to get core dump. If you could also add some info about the app and used extensions, that would be useful too.

hi: tks.
I have already opened process.dumpable. If there is progress, it will continue to follow up

 this is my php-fpm conf:
[global]
error_log = /proc/self/fd/2

; https://github.com/docker-library/php/pull/725#issuecomment-443540114
log_limit = 8192

[www]
; if we send this to /proc/self/fd/1, it never appears
access.log = /proc/self/fd/2

clear_env = no

; Ensure worker stdout and stderr are sent to the main error log.
catch_workers_output = yes
decorate_workers_output = no

[global]
error_log = /proc/self/fd/2
log_level = warning
emergency_restart_threshold = 30
emergency_restart_interval = 60s
process_control_timeout = 5s


[www]
access.log = /proc/self/fd/1
;listen = 127.0.0.1:9000
user = www-data
group = www-data
pm = dynamic
pm.max_children = 70
pm.start_servers = 30
pm.min_spare_servers = 30
pm.max_spare_servers = 70
pm.max_requests = 1000

request_terminate_timeout = 120
request_slowlog_timeout = 2s
slowlog = /proc/self/fd/2
rlimit_files = 51200
rlimit_core = 0


[global]
daemonize = no

[www]
listen = 9000

this is my php-ext enable:

[PHP Modules]
Core
ctype
curl
date
dom
fileinfo
filter
ftp
gd
hash
iconv
json
libxml
mbstring
mysqli
mysqlnd
openssl
pcre
PDO
pdo_mysql
pdo_sqlite
Phar
posix
readline
redis
Reflection
session
SimpleXML
sodium
SPL
sqlite3
standard
tokenizer
xml
xmlreader
xmlwriter
Zend OPcache
zlib

[Zend Modules]
Zend OPcache

Config looks ok so without core dump or re-creatable piece of code there is not much we can I'm afraid.

I will set status to Feedback which will close itself in 2 weeks or so if there is no further info. But we can always re-open it if you manage to get more info ;)

No feedback was provided. The bug is being suspended because
we assume that you are no longer experiencing the problem.
If this is not the case and you are able to provide the
information that was requested earlier, please do so and
change the status of the bug back to "Re-Opened". Thank you.