k5_mutex_lock: Received error 22 (Invalid argument)

[moore moore]

Hello,
I have a system using krb5-1.17 in a linux pthread multi threaded application acting as a proxy for many (1000s) clients using constrained delegation to webservices.TGT, TGS and AP are all working fine.
Under high thread concurrency it would appear ( ~ 200 threads ) and generally around ticket expiry/renewal, the following errors occur.
k5_mutex_lock: Received error 22 (Invalid argument)proxy_app: ../../../include/k5-thread.h:376: k5_mutex_lock: Assertion `r == 0' failed.k5_mutex_lock: Received error 22 (Invalid argument)k5_mutex_lock: Received error 22 (Invalid argument)k5_mutex_lock: Received error 22 (Invalid argument)proxy_app: ../../../include/k5-thread.h:376: k5_mutex_lock: Assertion `r == 0' failed.proxy_app: ../../../include/k5-thread.h:376: k5_mutex_lock: Assertion `r == 0' failed.
Is this a known issue? if not, I would be happy to try troubleshoot, patch and test with your guidance, suggestion.
Thank you.