Here's a follow up. This hung process is consuming 2 CPU cores worth of time.

top - 18:43:36 up 20:15,  2 users,  load average: 4.00, 4.01, 4.00
Tasks: 244 total,   1 running, 243 sleeping,   0 stopped,   0 zombie
%Cpu(s): 99.8 us,  0.2 sy,  0.0 ni,  0.0 id,  0.0 wa,  0.0 hi,  0.0 si
+,  0.0 st
MiB Mem :   3649.3 total,   2021.0 free,    485.4 used,   1142.8 buff/
+cache
MiB Swap:   7999.0 total,   7694.3 free,    304.7 used.   2853.8 avail
+ Mem 

    PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+
+ COMMAND                                                     
   6858 apache    20   0 2017692 131412  14080 S 199.7   3.5  91:09.18
+ /usr/sbin/httpd                                             
   4030 seann     20   0   18160   4456   4352 S   0.3   0.1   0:10.85
+ sshd                                                        
   7671 root      20   0  225244   3712   2944 R   0.3   0.1   0:00.02
+ top                                                         
      1 root      20   0  168760   9392   6016 S   0.0   0.3   1:56.96
+ systemd                                                     
      2 root      20   0       0      0      0 S   0.0   0.0   0:00.03
+ kthreadd
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and strace shows no system call activity.

proxy::</home/seann> strace -p 6858
strace: Process 6858 attached
read(5,
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