mod_cluster seg faults with DeterministicFailover On

Solution Unverified - Updated -


  • We run JBCS httpd with mod_cluster and are seeing frequent core dumps when using the DeterministicFailover option. Analysis of these show seg faults raised here by mod_cluster:
#0  proxy_worker_cmp (a=0x7ffb18002438, b=0x7ffb18002470) at mod_proxy_cluster.c:154
#1  0x00007ffba4c87ba3 in msort_with_tmp (p=0x7ffb551b37f0, b=0x7ffb551b3748, n=2) at msort.c:124
#2  0x00007ffba4c87b02 in msort_with_tmp (n=2, b=0x7ffb551b3748, p=0x7ffb551b37f0) at msort.c:45
#3  msort_with_tmp (p=0x7ffb551b37f0, b=0x7ffb551b3748, n=5) at msort.c:53
#4  0x00007ffba4c87ef7 in msort_with_tmp (n=5, b=, p=0x7ffb551b37f0) at msort.c:45
#5  __GI___qsort_r (b=b@entry=0x7ffb18002438, n=n@entry=5, s=s@entry=56, cmp=cmp@entry=0x7ffb90ae5e00 , arg=arg@entry=0x0) at msort.c:254
#6  0x00007ffba4c88148 in __GI_qsort (b=b@entry=0x7ffb18002438, n=n@entry=5, s=s@entry=56, cmp=cmp@entry=0x7ffb90ae5e00 ) at msort.c:308
#7  0x00007ffb90ae9ae7 in internal_find_best_byrequests (conf=0x55fe55cacb88, node_table=0x7ffb180108e0, context_table=0x7ffb1800fed8, 
    vhost_table=0x7ffb1802baa0, failoverdomain=0, domain=0x0, r=0x7ffb18006a10, balancer=0x55fe56065140) at mod_proxy_cluster.c:2331
#8  find_best_worker (balancer=0x55fe56065140, conf=conf@entry=0x55fe55cacb88, r=r@entry=0x7ffb18006a10, domain=domain@entry=0x0, 
    failoverdomain=failoverdomain@entry=0, vhost_table=vhost_table@entry=0x7ffb1802baa0, context_table=context_table@entry=0x7ffb1800fed8, 
    node_table=node_table@entry=0x7ffb180108e0, recurse=recurse@entry=1) at mod_proxy_cluster.c:3484
#9  0x00007ffb90aed611 in proxy_cluster_pre_request (worker=0x7ffb551b3b38, balancer=0x7ffb551b3b30, r=0x7ffb18006a10, conf=0x55fe55cacb88, 
    url=0x7ffb551b3b40) at mod_proxy_cluster.c:3851
#10 0x00007ffb9a409fa6 in proxy_run_pre_request () from /usr/jboss/jbossweb/shopapp_ws_m01/modules/
#11 0x00007ffb9a40ec62 in ap_proxy_pre_request () from /usr/jboss/jbossweb/shopapp_ws_m01/modules/
#12 0x00007ffb9a40a7dc in proxy_handler () from /usr/jboss/jbossweb/shopapp_ws_m01/modules/


  • JBoss Core Services (JBCS) httpd 2.4.29
  • mod_cluster 1.3.8
  • JBoss Enterprise Application Platform (EAP) 7.x

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