HP UX的日志中发现下面的错误:

empo007

syslog.log上发现的错误为:
Feb  6 09:24:28 bfjs_tx vmunix: DIAGNOSTIC SYSTEM WARNING:
Feb  6 09:24:28 bfjs_tx vmunix:    The diagnostic logging facility is no longer receiving excessive
Feb  6 09:24:28 bfjs_tx vmunix:    errors from the I/O subsystem.  8 I/O error entries were lost.
dmesg的错误信息如下:
DIAGNOSTIC SYSTEM WARNING:
   The diagnostic logging facility has started receiving excessive
   errors from the I/O subsystem.  I/O error entries will be lost
   until the cause of the excessive I/O logging is corrected.
   If the diaglogd daemon is not active, use the Daemon Startup command
   in stm to start it.
   If the diaglogd daemon is active, use the logtool utility in stm
   to determine which I/O subsystem is logging excessive errors.

提示用STM进行诊断,请问如何诊断,STM是个什么工具?
谢谢!