listener error - connections failing or are slow

Oracle 10g; Windows 2003 server

This server/db is about 2 weeks old. It was working fine but now the connection to db are getting real slow or they are failing most of the times. The error it shows are:
TNS-12571: TNS:packet writer failure
TNS-12560: TNS:protocol adapter error
TNS-00530: Protocol adapter error
32-bit Windows Error: 54: Unknown error
TNS-12500: TNS:listener failed to start a dedicated server process

See this from actual listener.log:
-------------------------------
29-AUG-2006 10:12:17 * 12502
TNS-12502: TNS:listener received no CONNECT_DATA from client
29-AUG-2006 10:12:17 * 12502
TNS-12502: TNS:listener received no CONNECT_DATA from client
29-AUG-2006 10:12:17 * (CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=MYDB)(CID=(PROGRAM=D:\oracle\product\10g\db_1\bin\nmup m.exe)(HOST=MYDB)(USER=SYSTEM))) * (ADDRESS=(PROTOCOL=tcp)(HOST=IPADDRESS)(PORT=2380)) * establish * MYDB * 12571
TNS-12571: TNS:packet writer failure
TNS-12560: TNS:protocol adapter error
TNS-00530: Protocol adapter error
32-bit Windows Error: 54: Unknown error
TNS-12500: TNS:listener failed to start a dedicated server process
TNS-12560: TNS:protocol adapter error
29-AUG-2006 10:13:39 * (CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=MYDB)(CID=(PROGRAM=D:\oracle\product\10g\db_1\bin\nmup m.exe)(HOST=MYDB)(USER=SYSTEM))) * (ADDRESS=(PROTOCOL=tcp)(HOST=IPADDRESS)(PORT=2383)) * establish * MYDB * 0
29-AUG-2006 10:13:39 * (CONNECT_DATA=(SID=MYDB)(CID=(PROGRAM=D:\oracle\product\10g\db_1\perl\5.6.1\bin\MSWin32-x86\perl.exe)(HOST=MYDB)(USER=SYSTEM))) * (ADDRESS=(PROTOCOL=tcp)(HOST=IPADDRESS)(PORT=2385)) * establish * MYDB * 0
------------------------------------

After listener restart, it worked fine for few minutes and then started showing errors like before. There is no error in sqlnet.log file.

Please suggest whats going wrong here and its fix. I have 5 other servers like that and they are all working fine.
-D

I'd look at memory on the server.

Quote:

---

Originally Posted by marist89

I'd look at memory on the server.

---

Memory is not the issue. There is plenty. The difference that I noticed between this server/db and other working servers/db is that they are not MTS setup but this one is has these entries in registry.

HKEY_LOCAL_MACHINE\SOFTWARE\ORACLE\OracleMTSRecoveryService

ORAMTS_NET_CACHE_MAXFREE = 5
ORAMTS_NET_CACHE_TIMEOUT = 120000
ORAMTS_OSCREDS_MATCH_LEVEL = OS_AUTH_LOGIN
ORAMTS_SESS_TXNTIMETOLIVE = 120

Also heer is my TNSNAMES.ora entry on server:
------------------------------------------------
MYDB =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = MYSERVER)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = MYDB)
)
)

and, LISTENER.ora entry
-------------------------------------------
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = D:\oracle\product\10g\db_1)
(PROGRAM = extproc)
)
(SID_DESC =
(GLOBAL_DBNAME = MYDB)
(ORACLE_HOME = D:\oracle\product\10g\db_1)
(SID_NAME = MYDB)
)
)

LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC))
)
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = MYSERVER)(PORT = 1521))
)
)
)


-D