We recently saw some strange behvior in pvfs2-client-core when a server goes 
away 
(via segfault) and the client is unable to re-mount the filesystem. The 
pvfs2-client-core process takes up 100% of a core just spinning on 
process_vfs_request -> PVFS_sys_testsome and subsequent calls. Full backtrace 
follows. 

In looking at the code in pvfs2-client-core it seems to  assume that the 
re-mount 
will always succeed (around line 3579). However, I don't know that it's the 
root 
cause of the issue. I'll continue looking but wondered if anyone had ideas on 
this. 
This appears to be re-creatable by:
1) cleanly mounting and using the filesystem for some I/O
2) either killing the servers or adding iptables rules to the client to reject 
traffic to the server,
3) Attemping I/O from the client

The operation correctly dies with connection refused but the client begins to 
spin 
taking up CPU.

(gdb) bt
#0  0x00511402 in __kernel_vsyscall ()
#1  0x001d8023 in poll () from /lib/libc.so.6
#2  0x0082ebed in PINT_dev_test_unexpected (incount=5, outcount=0xbf84e4f8, 
info_array=0x8bbbc0, max_idle_time=10) at src/io/dev/pint-dev.c:398
#3  0x00848f50 in PINT_thread_mgr_dev_push (max_idle_time=10) at 
src/io/job/thread-mgr.c:332
#4  0x00844caf in do_one_work_cycle_all (idle_time_ms=10) at 
src/io/job/job.c:5238
#5  0x008454a1 in job_testcontext (out_id_array_p=0xbf8515f0, 
inout_count_p=0xbf8521f4, returned_user_ptr_array=0xbf851df4, 
out_status_array_p=0xbf84e5f0, timeout_ms=10, context_id=0) at 
src/io/job/job.c:4273
#6  0x00857dba in PINT_client_state_machine_testsome (op_id_array=0xbf8522a8, 
op_count=0xbf8528c4, user_ptr_array=0xbf8527a8, error_code_array=0xbf8526a8, 
timeout_ms=10) at src/client/sysint/client-state-machine.c:756
#7  0x00857fb9 in PVFS_sys_testsome (op_id_array=0xbf8522a8, 
op_count=0xbf8528c4, user_ptr_array=0xbf8527a8, error_code_array=0xbf8526a8, 
timeout_ms=10) at src/client/sysint/client-state-machine.c:971
#8  0x08050cd6 in process_vfs_requests () at 
src/apps/kernel/linux/pvfs2-client-core.c:3119
#9  0x08052658 in main (argc=10, argv=0xbf852a74) at 
src/apps/kernel/linux/pvfs2-client-core.c:3579

Let me now if more information is needed, thanks for the input!

Michael
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