plockstat(1M) System Administration Commands plockstat(1M)NAMEplockstat - report user-level lock statistics
SYNOPSISplockstat [-vACHV] [-n count] [-s depth] [-e secs]
[-x arg [=val]] command [arg]...
plockstat [-vACHV] [-n count] [-s depth] [-e secs]
[-x arg [=val]] -p pid
DESCRIPTION
The plockstat utility gathers and displays user-level locking statis‐
tics. By default, plockstat monitors all lock contention events, gath‐
ers frequency and timing data about those events, and displays the data
in decreasing frequency order, so that the most common events appear
first.
plockstat gathers data until the specified command completes or the
process specified with the -p option completes.
plockstat relies on DTrace to instrument a running process or a command
it invokes to trace events of interest. This imposes a small but mea‐
surable performance overhead on the processes being observed. Users
must have the dtrace_proc privilege and have permission to observe a
particular process with plockstat. Refer to the for more information
about DTrace security features.
OPTIONS
The following options are supported:
-A Watch all lock events. This option is equivalent to
-CH.
-C Watch contention events.
-H Watch hold events.
-e secs Exit after the number of seconds specified have
elapsed.
-n count Display only the specified number of entries for each
output category.
-s depth Record a stack trace rather than just the calling func‐
tion.
-p pid Specify a process ID from which plockstat is to gather
data.
-v Print out a message to indicate that tracing has
started.
-x arg[=val] Enable or modify a DTrace runtime option or D compiler
option. The list of options is found in the Solaris
Dynamic Tracing Guide. Boolean options are enabled by
specifying their name. Options with values are set by
separating the option name and value with an equals
sign (=).
-V Print the Dtrace commands used to gather the data. The
output can then be used directly with the dtrace(1M)
command.
OPERANDS
The following operands are supported:
arg A string to be passed as an argument to command.
command The name of a utility to be invoked.
count A positive integer value.
pid A process identifier for a process to be monitored.
secs Duration specified as a positive integer number of seconds.
DISPLAY HEADERS
The following headers appear over columns of data in plockstat output.
Count
Number of times an event occurred.
nsec
Average duration of an event, in nanoseconds.
Lock
Address of a lock, displayed symbolically if possible.
Caller
Address of a caller, displayed symbolically if possible.
EXIT STATUS
The following exit values are returned:
0 Successful completion.
>0 An error occurred.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Availability │developer/dtrace │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │See below. │
└─────────────────────────────┴─────────────────────────────┘
The command-line syntax is Committed. The human-readable output is
Uncommitted.
SEE ALSOdtrace(1M), lockstat(1M), mutex_init(3C), pthread_mutex_lock(3C),
pthread_rwlock_rdlock(3C), pthread_rwlock_wrlock(3C),
pthread_rwlock_unlock(3C), rwlock(3C), attributes(5), fasttrap(7D)SunOS 5.11 12 Oct 2009 plockstat(1M)