Commented by: @SENikitin

Hi,

Problem still exists - we have tested it with yesterday snapshot, Firebird SuperClassic hanged again, dump and pdb are here:
http://ge.tt/2F4o2aM2/v/0?c

Commented by: @AlexPeshkoff

I can't use dmp & pdb - I have no windows OS. Please provide stack traces text dump.

Commented by: @dyemanov

thread 1:

Jrd::Service::Service(const char * service_name=0x0000000000200000, unsigned short spb_length=32, const unsigned char * spb_data=0x5f65636976726573)
*** hangs at dbInitGuard.enter(), file svc.cpp, line 812
jrd8_service_attach(__int64 * user_status=0x000000000198f6f0, const char * service_name=0x000000000198f6f0, Jrd::Service * * svc_handle=0x00000000051b8a08, unsigned short spb_length=0, const char * spb=0x000000000198f8a0)

thread 2:

Jrd::SecurityDatabase::init()
*** hangs at MutexLockGuard guard(mutex), file pwd.cpp, line 248
getUserInfo(Jrd::UserId & user={...}, const DatabaseOptions & options={...})
jrd8_attach_database(__int64 * user_status=0x0000000140000000, const char * filename=0x0000000004d0f560, Jrd::Attachment * * handle=0x00000000051be1d0, short dpb_length=-7728, const unsigned char * dpb=0x0000000004d0f610)

thread 3:

jrd8_attach_database(__int64 * user_status=0x0000000140000000, const char * filename=0x000000000490e270, Jrd::Attachment * * handle=0x000000000000000c, short dpb_length=-6640, const unsigned char * dpb=0x000000000490e320)
*** hangs at guardDbInit.enter(), file jrd.cpp, line 921
isc_attach_database(__int64 * user_status=0x000000000490e530, short file_length=31, const char * file_name=0x000000000490ed01, unsigned int * public_handle=0x000000000490ebb0, short dpb_length=12, const char * dpb=0x000000000490e570)
Jrd::SecurityDatabase::prepare()
Jrd::SecurityDatabase::lookupUser(const char * user_name=0x00000000778eb950, int * uid=0x000000000490e990, int * gid=0x0000000000000006, char * pwd=0x000000000490ebb0)
Jrd::SecurityDatabase::verifyUser(const char * user_name=0x0000000000829ab8, const char * password=0x0000000000000000, const char * password_enc=0x000000000082b498, int * uid=0x0000000140375949, int * gid=0x000000000490ed78, int * node_id=0x000000000490ecf0, const Firebird::StringBaseFirebird::StringComparator\ & remoteId={...})
Jrd::Service::Service(const char * service_name=0x0000000100200000, unsigned short spb_length=32, const unsigned char * spb_data=0x5f65636976726573)
jrd8_service_attach(__int64 * user_status=0x000000000490f6f0, const char * service_name=0x000000000490f6f0, Jrd::Service * * svc_handle=0x0000000000829288, unsigned short spb_length=0, const char * spb=0x000000000490f8a0)

Commented by: @dyemanov

SecurityDatabase::lookupUser() holds pwd::mutex and acquires dbInitMutex inside prepare()->jrd8_attach_database
Service::Service() holds dbInitGuard and acquires pwd::mutex inside SecurityDatabase::init() (via siHolder).