After upgrade to Wildfly 10.1 from Wildfly 10.0 i have file descriptors leak on production environment. I have same configuration on both 10.0 and 10.1.
Previously, 10.0 version has file descriptors leak too. I was able to reproduce this leak by physically terminate connection from the client - after that, all descriptors, taked by this client, are stay occupied forever. I fix this leak by adding tcp-keep-alive="true" to http-listener ([WFLY-3536] Wildfly 8.1.0 Final keeps established connections forever - JBoss Issue Tracker ).
Then I was faced with memory leak in SSL ([WFLY-6380] Memory leak and freeze (io.undertow.protocols.ssl.SslConduit) - JBoss Issue Tracker ) and decide to upgrade to 10.1 version.
The 10.1 has file descriptors leak with another symptoms, and faster, than in 10.0. I run lsof command and see many records with CLOSE_WAIT, like (changed real domain to myhost.com):
java 29821 root 4089u IPv4 462742734 0t0 TCP myhost.com:https->37-221-202-146.obit.ru:6821 (CLOSE_WAIT)
java 29821 root 3236u IPv4 462731802 0t0 TCP myhost.com:http->baiduspider-180-76-15-148.crawl.baidu.com:14464 (CLOSE_WAIT)
Note, that there is both - http and https protocols.
Another bunch of records is:
java 29821 root 3217u sock 0,6 0t0 462731371 can't identify protocol
File descriptors count grow to 2500-4500 and after that server not response to incoming connections, but inner jobs works perfectly.
I can't reproduce this leak on test environment. I do load testing and connection terminating, but descriptors count not grown above 1700 and i don't see records with "CLOSE_WAIT" or "can't identify protocol". I'l stopped 10.1 version and run 10.0 version on the production server, and don't see "CLOSE_WAIT" or "can't identify protocol" records at all.
The only difference in http settings compared with clean installation - is adding "tcp-keep-alive="true" read-timeout="60000" write-timeout="60000"" to http-listener and https-listener. This settings migrated from 10.0 to fix WFLY-3536.
What can i do to prevent file descriptors leak on Wildfly 10.1?