package debug
Import Path
runtime/debug (on golang.org and go.dev)
Dependency Relation
imports 5 packages, and imported by one package
Involved Source Files
garbage.go
mod.go
d-> stack.go
stubs.go
debug.s
Exported Type Names
Exported Values
func
FreeOSMemory()
FreeOSMemory forces a garbage collection followed by an
attempt to return as much memory to the operating system
as possible. (Even if this is not called, the runtime gradually
returns memory to the operating system in a background task.)
func
PrintStack()
PrintStack prints to standard error the stack trace returned by runtime.Stack.
func
ReadBuildInfo() (info *
BuildInfo, ok
bool)
ReadBuildInfo returns the build information embedded
in the running binary. The information is available only
in binaries built with module support.
func
ReadGCStats(stats *
GCStats)
ReadGCStats reads statistics about garbage collection into stats.
The number of entries in the pause history is system-dependent;
stats.Pause slice will be reused if large enough, reallocated otherwise.
ReadGCStats may use the full capacity of the stats.Pause slice.
If stats.PauseQuantiles is non-empty, ReadGCStats fills it with quantiles
summarizing the distribution of pause time. For example, if
len(stats.PauseQuantiles) is 5, it will be filled with the minimum,
25%, 50%, 75%, and maximum pause times.
func
SetGCPercent(percent
int)
int
SetGCPercent sets the garbage collection target percentage:
a collection is triggered when the ratio of freshly allocated data
to live data remaining after the previous collection reaches this percentage.
SetGCPercent returns the previous setting.
The initial setting is the value of the GOGC environment variable
at startup, or 100 if the variable is not set.
A negative percentage disables garbage collection.
func
SetMaxStack(bytes
int)
int
SetMaxStack sets the maximum amount of memory that
can be used by a single goroutine stack.
If any goroutine exceeds this limit while growing its stack,
the program crashes.
SetMaxStack returns the previous setting.
The initial setting is 1 GB on 64-bit systems, 250 MB on 32-bit systems.
SetMaxStack is useful mainly for limiting the damage done by
goroutines that enter an infinite recursion. It only limits future
stack growth.
func
SetMaxThreads(threads
int)
int
SetMaxThreads sets the maximum number of operating system
threads that the Go program can use. If it attempts to use more than
this many, the program crashes.
SetMaxThreads returns the previous setting.
The initial setting is 10,000 threads.
The limit controls the number of operating system threads, not the number
of goroutines. A Go program creates a new thread only when a goroutine
is ready to run but all the existing threads are blocked in system calls, cgo calls,
or are locked to other goroutines due to use of runtime.LockOSThread.
SetMaxThreads is useful mainly for limiting the damage done by
programs that create an unbounded number of threads. The idea is
to take down the program before it takes down the operating system.
func
SetPanicOnFault(enabled
bool)
bool
SetPanicOnFault controls the runtime's behavior when a program faults
at an unexpected (non-nil) address. Such faults are typically caused by
bugs such as runtime memory corruption, so the default response is to crash
the program. Programs working with memory-mapped files or unsafe
manipulation of memory may cause faults at non-nil addresses in less
dramatic situations; SetPanicOnFault allows such programs to request
that the runtime trigger only a panic, not a crash.
SetPanicOnFault applies only to the current goroutine.
It returns the previous setting.
func
SetTraceback(level
string)
SetTraceback sets the amount of detail printed by the runtime in
the traceback it prints before exiting due to an unrecovered panic
or an internal runtime error.
The level argument takes the same values as the GOTRACEBACK
environment variable. For example, SetTraceback("all") ensure
that the program prints all goroutines when it crashes.
See the package runtime documentation for details.
If SetTraceback is called with a level lower than that of the
environment variable, the call is ignored.
func
Stack() []
byte
Stack returns a formatted stack trace of the goroutine that calls it.
It calls runtime.Stack with a large enough buffer to capture the entire trace.
func
WriteHeapDump(fd
uintptr)
WriteHeapDump writes a description of the heap and the objects in
it to the given file descriptor.
WriteHeapDump suspends the execution of all goroutines until the heap
dump is completely written. Thus, the file descriptor must not be
connected to a pipe or socket whose other end is in the same Go
process; instead, use a temporary file or network socket.
The heap dump format is defined at https://golang.org/s/go15heapdump.
