splat 명령

Splat는 AIX 추적 명령을 통해 수집된 AIX 추적 파일을 1차 입력으로 간주합니다. splat로 추적을 분석하기 전에 추적이 다음을 포함하여 적당한 후크 세트로 수집되는지 확인해야 합니다.

106 DISPATCH
10C DISPATCH IDLE PROCESS
10E RELOCK
112 LOCK
113 UNLOCK
134 HKWD_SYSC_EXECVE
139 HKWD_SYSC_FORK
419 CPU PREEMPT
465 HKWD_SYSC_CRTHREAD
46D WAIT LOCK
46E WAKEUP LOCK
606 HKWD_PTHREAD_COND
607 HKWD_PTHREAD_MUTEX
608 HKWD_PTHREAD_RWLOCK
609 HKWD_PTHREAD_GENERAL

이 잠금 및 잠금 해제 추적 이벤트를 캡처하면 멀티프로세서 환경에서 사용되는 잠금 빈도에 따라 심각한 성능 저하를 야기할 수 있습니다. 따라서, 잠금 추적 이벤트 보고는 주로 사용 안함으로 설정됩니다. 잠금 추적 이벤트 보고를 사용 가능하게 하려면 splat에 필요한 잠금 추적 이벤트를 포함하게 될 추적이 수집되기 전에 다음 단계를 수행해야 합니다(KornShell 구문).

  1. bosboot -ad /dev/hdisk0 -L

  2. shutdown -Fr

  3. (reboot the machine)

  4. locktrace -S

  5. mkdir temp.lib; cd temp.lib

  6. ln -s /usr/ccs/lib/perf/libpthreads.a

  7. export LIBPATH=$PWD:$LIBPATH

단계 1 - 3은 선택사항입니다. 이 단계에서는 주소 대신에 커널 잠금 클래스 이름 표시가 사용 가능합니다. bosboot 및 해당 플래그에 대한 자세한 정보는 bosboot(1)의 내용을 참조하십시오. 5 - 7 단계는 사용자 pthread 잠금 계기를 활성화하기 위해 필요합니다. temp.lib 서브디렉토리는 어딘가에 놓여질 수 있습니다. 1 - 7 단계는 보고서 완료에 반드시 필요합니다.

splat에서 생성한 보고서는 보고서 요약, 잠금 요약 보고서 섹션 및 잠금 세부사항 보고서의 리스트로 구성되고 각각에는 연관된 기능 세부사항 및/또는 스레드 세부사항 보고서가 있을 수 있습니다.

Report Summary
^^^^^^^^^^^^^^
 The report summary consists of the following elements:

 - The trace command used to collect the trace.
 - The host that the trace was taken on.
 - The date that the trace was taken on.
 - The duration of the trace in seconds.
 - The estimated number of CPUs
 - The combined elapsed duration of the trace in seconds;
   ( the duration of the trace multiplied by the number of
     CPUs identified during the trace ).
 - Start time, which is the offset in seconds from the beginning of the
   trace that trace statistics begin to be gathered.
 - Stop time, which is the offset in seconds from the beginning of the
   trace that trace statistics stop being gathered.
 - Total number of acquisitions during the trace.
 - Acquisitions per second, which is computed by dividing
   the total number of lock acquisitions by the real-time
   duration of the trace.
 - % of Total Spin Time, this is the summation of all lock spin hold
   times, divided by the combined trace duration in seconds, divided by 100.
   The current goal is to have this value be less than 10% of the total
   trace duration.


 Lock Summary
 ^^^^^^^^^^^^

 The lock summary report has the following fields:

Lock		         The name, lockclass or address of the lock.


Type              The type of the lock, identified by one of the following letters: 
                      Q    A RunQ lock 
                      S    A simple kernel lock 
                      D    A disabled simple kernel lock
                      C    A complex kernel lock 
                      M    A PThread mutex 
                      V    A PThread condition-variable 
                      L    A PThread read/write lock
Acquisitions     The number of successful lock attempts for this lock, minus
                  the number of times a thread was preempted while holding
                  this lock.

Spins            The number of unsuccessful lock attempts for this lock,
                  minus the number of times a thread was undispatched while
                  spinning.

Wait             The number of unsuccessful lock attempts that
 or               resulted in the attempting thread going to
Transform         sleep to wait for the lock to become available,
                  or allocating a krlock.

%Miss            Spins divided by Acquisitions plus Spins, multiplied by 100.

%Total           Acquisitions divided by the total number of all
                  lock acquisitions, multiplied by 100.

Locks/CSec       Acquisitions divided by the combined elapsed
 	               duration in seconds.

Percent HoldTime 
Real CPU          The percent of combined elapsed trace time that
                  threads held the lock in question while dispatched.
                  DISPATCHED_HOLDTIME_IN_SECONDS divided by combined
                  trace duration, multiplied by 100.

Real Elaps(ed)    The percent of combined elapsed trace time that
                  threads held the lock while dispatched or sleeping.
                  UNDISPATCHED_AND_DISPATCHED_HOLDTIME_IN_SECONDS divided
                  by combined trace duration, multiplied by 100.

Comb Spin         The percent of combined elapsed trace time that
                  threads spun while waiting to acquire this lock.
                  SPIN_HOLDTIME_IN_SECONDS divided by combined trace
                  duration, multiplied by 100.

퍼센트 회전 보류 시간에 의해 내림차순으로 분류된 10개의 잠금 리스트에 대한 잠금 요약 보고서 디폴트 값(10번째 필드). 요약 보고서의 길이는 -S 전환을 사용하여 조정될 수 있습니다. 요약 보고서(및 다른 모든 보고서)의 정렬 순서는 옵션이 SORTING 도움말 섹션, splat -h 정렬에서 설명된 -s 전환으로 설정될 수 있습니다.

Lock Detail
^^^^^^^^^^^

 The lock detail report consists of the following fields:

 LOCK             The address (in hexadecimal) of the lock.

 NAME             The symbol mapping for that address (if available)

 CLASS            The lockclass name (if available) and hexadecimal offset,
                  used to allocate this lock ( lock_alloc() kernel service ).

Parent Thread    Thread id of the parent thread. This field only exists for Mutex, 
                  Read/Write lock and Conditional Variable report. 

 creation time    Elapsed time in seconds after the first event recorded in trace, 
                  if available. This field only exists for Mutex, Read/Write lock
                  and Conditional Variable report.
 deletion time    Elapsed time in seconds after the first event recorded in trace, 
                  if available. Tthis field only exists for Mutex, Read/Write lock
                  and Conditional Variable report. 

 Pid              Pid number associated to the lock (this field only exists for Mutex, 
                  Read/Write lock and Conditional Variable report). 

 Process Name    Process name associated to the lock (this field only exists for Mutex, 
                 Read/Write lock and Conditional Variable report). 

 Call-Chain      Stack of called methods (if possible to have them, this field only 
                 exists for Mutex, Read/Write lock and Conditional Variable report). 


 Acquisitions     The number of successful lock attempts for this lock.
                  This field is named Passes for the conditional variable lock report.

 Miss Rate        The number of unsuccessful lock attempts divided by
                  Acquisitions plus unsuccessful lock attempts, multiplied
                  by 100.

 Spin Count       The number of unsuccessful lock attempts.

 Wait Count       The number of unsuccessful lock attempts that resulted in
                  the attempting thread going to sleep to wait for the lock
                  to become available.

 Transform Count  The number of krlock allocated and deallocated by the simple lock. 

 Busy Count	      The number of simple_lock_try() calls that returned busy.

 Seconds Held
 CPU              The total time in seconds that this lock was held by
                  dispatched threads.

 Elapsed	         The total time in seconds that this lock was held by
                  both dispatched and undispatched threads.

NOTE: neither of these two values should exceed the
      total real elapsed duration of the trace.

 Percent Held
 Real CPU         The percent of combined elapsed trace time that
                  threads held the lock in question while dispatched.
                  DISPATCHED_HOLDTIME_IN_SECONDS divided by trace
                  duration, multiplied by 100.

 Real Elaps(ed)   The percent of combined elapsed trace time that
                  threads held the lock while dispatched or sleeping.
                  UNDISPATCHED_AND_DISPATCHED_HOLDTIME_IN_SECONDS divided
                  by trace duration, multiplied by 100.

 Comb Spin        The percent of combined elapsed trace time that
                  threads spun while waiting to acquire this lock.
                  SPIN_HOLDTIME_IN_SECONDS divided by trace duration,
                  multiplied by 100. 

 Wait             The percentage of combined elapsed trace time that 
                  threads unsuccessfully tried to acquire this lock.

 SpinQ            Splat keeps track of the minimum, maximum and average
                  depth of the spin queue (the threads spinning, waiting
                  for a lock to become available).

 WaitQ            As with the spin queue, splat also tracks the minimum,
                  maximum and average depth of the queue of threads waited
                  waiting for a lock to become available).

PROD              The associated krlocks prod calls count.

CONFER SELF       The confer to self calls count for the simple lock and the 
                  associated krlocks.

CONFER TARGET     The confer to target calls count for the simple lock and the 
                  associated krlocks. w/ preemption reports the successfull calls 
                  count, resulting in a preemption.

CONFER ALL        The confer to all calls count for the simple lock and the 
                  associated krlocks. w/ preemption reports the successfull calls 
                  count, resulting in a preemption.

HANDOFF           The associated krlocks handoff calls count.

Lock Activity w/Interrupts Enabled (mSecs)

잠금 세부사항 보고서의 이 섹션은 밀리초로 표시된 시간에 splat이 각 잠금에 대해 수집하는 원시 데이터의 덤프입니다. 다섯 개의 상태: LOCK, SPIN, WAIT, UNDISP(atched) 및 PREEMPT는 splat의 사용 가능한 simple_lock 유한 상태 머신의 다섯 가지 기본 상태입니다. 각 상태의 개수는 스레드의 조치가 해당 상태 안으로 결과적으로 전이가 된 횟수입니다. 지속 시간(밀리초)은 잠금 요청이 해당 상태에서 사용한 최소, 최대, 평균 및 총계 시간량을 표시합니다.

   LOCK:    this state represents a thread successfully acquiring a lock.

   SPIN:    this state represents a thread unsuccessfully trying to acquire
            a lock.

   WAIT:    this state represents a spinning thread (in SPIN) going to sleep
            (voluntarily) after exceeding the thread's spin threshold.

   UNDISP:  this state represents a spinning thread (in SPIN) becoming
            undispatched (involuntarily) before exceeding the thread's
            spin threshold.

   PREEMPT: this state represents when a thread holding a lock is
            undispatched.


Lock Activity w/Interrupts Disabled (mSecs)

잠금 세부사항 보고서의 이 섹션은 밀리초로 표시된 시간에 splat이 각 잠금에 대해 수집하는 원시 데이터의 덤프입니다. 여섯 개의 상태: LOCK, SPIN, KRLOCK을 가지는 LOCK, KRLOCK LOCK, KRLOCK SPIN 및 TRANSFORM은 splat의 사용 불가능한 simple_lock 유한 상태 머신의 여섯 개의 기본 상태입니다. 각 상태의 개수는 스레드의 조치가 해당 상태 안으로 결과적으로 전이가 된 횟수입니다. 지속 시간(밀리초)은 잠금 요청이 해당 상태에서 사용한 최소, 최대, 평균 및 총계 시간량을 표시합니다.

LOCK:        This state represents a thread successfully acquiring a lock.

SPIN:        This state represents a thread unsuccessfully trying to acquire
             a lock.

LOCK with    The thread has successfully acquired the lock, while holding 
 KRLOCK:     the associated krlock, and is currently executing.

KRLOCK LOCK: The thread has successfully acquired the associated krlock, 
             and is currently executing.

KRLOCK SPIN: The thread is executing and unsuccessfully attempting to acquire
             the associated krlock. 

TRANSFORM:   The thread has successfully allocated a krlock it associates to, 
             and is executing.


Function Detail
^^^^^^^^^^^^^^^

 The function detail report consists of the following fields:

 Function Name   The name or return address of the function which
                 used the lock.

 Acquisitions	   The number of successful lock attempts for this lock.
                 For complex lock and read/write lock there is a 
                 distinction between acquisition for writing 
                 (Acquisition Write) and for reading 
                 (Acquisition Read).


 Miss Rate      The number of unsuccessful lock attempts divided by
                Acquisitions, multiplied by 100.

 Spin Count     The number of unsuccessful lock attempts.
                For complex lock and read/write lock there is a 
                distinction between spin count for writing 
                (Spin Count Write) and for reading 
                (Spin Count Read).

 Wait Count     The number of unsuccessful lock attempts that resulted in
                the attempting thread going to sleep to wait for the lock
                to become available.
                For complex lock and read/write lock there is a 
                distinction between wait count for writing 
                (Wait Count Write) and for reading 
                (Wait Count Read).

Transform Count The number of times that a simple lock has allocated a krlock,
                while the thread was trying to acquire the simple lock.

 Busy Count	     The number of simple_lock_try() calls that returned busy.

 Percent Held of Total Time 
 CPU              The percent of combined elapsed trace time that
                  threads held the lock in question while dispatched.
                  DISPATCHED_HOLDTIME_IN_SECONDS divided by trace
                  duration, multiplied by 100.

 Elaps(ed)	      The percent of combined elapsed trace time that
                  threads held the lock while dispatched or sleeping.
                  UNDISPATCHED_AND_DISPATCHED_HOLDTIME_IN_SECONDS divided
                  by trace duration, multiplied by 100.

 Spin             The percent of combined elapsed trace time that
                  threads spun while waiting to acquire this lock.
                  SPIN_HOLDTIME_IN_SECONDS divided by combined trace
                  duration, multiplied by 100.

 Wait             The percentage of combined elapsed trace time that 
                  threads unsuccessfully tried to acquire this lock. 

 Return Address   The calling function's return address in hexadecimal.

 Start Address	   The start address of the calling function in hexadecimal.

 Offset           The offset from the function start address in hexadecimal.


Thread Detail
^^^^^^^^^^^^^

The thread detail report consists of the following fields:

 ThreadID        Thread identifier.

 Acquisitions    The number of successful lock attempts for this lock.

 Miss Rate       The number of unsuccessful lock attempts divided by
                 Acquisitions, multiplied by 100.

 Spin Count      The number of unsuccessful lock attempts.

 Wait Count      The number of unsuccessful lock attempts that resulted in
                 the attempting thread going to sleep to wait for the lock
                 to become available.

Transform Count The number of times that a simple lock has allocated a krlock,
                while the thread was trying to acquire the simple lock.

Busy Count      The number of simple_lock_try() calls that returned busy.

 Percent Held of Total Time 
 CPU              The percent of combined elapsed trace time that
                  threads held the lock in question while dispatched.
                  DISPATCHED_HOLDTIME_IN_SECONDS divided by trace
                  duration, multiplied by 100.

 Elaps(ed)        The percent of combined elapsed trace time that
                  threads held the lock while dispatched or sleeping.
                  UNDISPATCHED_AND_DISPATCHED_HOLDTIME_IN_SECONDS divided
                  by trace duration, multiplied by 100.

 Spin             The percent of combined elapsed trace time that
                  threads spun while waiting to acquire this lock.
                  SPIN_HOLDTIME_IN_SECONDS divided by combined trace
                  duration, multiplied by 100. 

 Wait             The percent of combined elapsed trace time that 
                  threads unsuccessfully tried to acquire this lock. 

 ProcessID        Process identifier (only for SIMPLE and COMPLEX Lock report). 

 Process Name     Name of the process (only for SIMPLE and COMPLEX Lock report).

splat을 사용하여 사용자는 -s 옵션을 사용하여 세부사항 보고서를 잠그고 요약을 정렬하는 데 사용되는 기준을 지정할 수 있습니다. 디폴트 분류 기준은 퍼센트 회전 보류 시간에 따라 분류되고, 이는 결합된 추적 지속 시간과 비교되는 잠금에 대한 회전에 스레드가 사용된 시간의 비율입니다. -s를 사용하여 분류 기준이 다음으로 변경될 수 있습니다.