WebCenter Sites - Apache Web Server - Stuck Threads (Deadlock) (Doc ID 2239469.1)

Last updated on JUNE 06, 2023

Applies to:

Symptoms

On 12.2.1.0.0 version, WebCenter Sites, seeing Stuck Threads when accessing from Apache 2.2, as seen in the HTTP Thread Analysis.

The HTTP Thread Analysis provided shows the Apache Module mod_status statistics, which revealed that there were several POST/GET requests stuck in Mode of Operation "W" Sending Reply, such as:

Srv PID Acc M CPU SS Req Conn Child Slot Client VHost Request
13-2 8328 16/16/24 W 0.01 81529 0 0.6 0 3.49 12.13.14.100.1 mysite.example.com POST /visitors-webapp/rest/v1/visitor/getId HTTP/1.1
16-2 9463 0/12/57 W 0.11 80636 0 0 0.24 3.09 12.13.14.100.86 mysite.example..com GET /sites/mypages/newhtml HTTP/1.1

Srv Child Server number - generation
PID OS process ID
Acc Number of accesses this connection / this child / this slot
M Mode of operation
CPU CPU usage, number of seconds
SS Seconds since beginning of most recent request
Req Milliseconds required to process most recent request
Conn Kilobytes transferred this connection
Child Megabytes transferred this child
Slot Total megabytes transferred this slot

-----------------------------------------------------------------------------
Mode of Operation (M) values

"_" Waiting for Connection, "S" Starting up, "R" Reading Request,
"W" Sending Reply, "K" Keepalive (read), "D" DNS Lookup,
"C" Closing connection, "L" Logging, "G" Gracefully finishing,
"I" Idle cleanup of worker, "." Open slot with no current process
-----------------------------------------------------------------------------

Cause

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