8203469: Faster safepoints
Reviewed-by: dcubed, pchilanomate, dholmes, acorn, coleenp, eosterlund
/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
#include "precompiled.hpp"
#include "classfile/classLoader.hpp"
#include "logging/log.hpp"
#include "runtime/timer.hpp"
#include "runtime/vm_version.hpp"
#include "services/attachListener.hpp"
#include "services/management.hpp"
#include "services/runtimeService.hpp"
#include "utilities/dtrace.hpp"
#include "utilities/exceptions.hpp"
#include "utilities/macros.hpp"
#if INCLUDE_MANAGEMENT
TimeStamp RuntimeService::_app_timer;
TimeStamp RuntimeService::_safepoint_timer;
PerfCounter* RuntimeService::_sync_time_ticks = NULL;
PerfCounter* RuntimeService::_total_safepoints = NULL;
PerfCounter* RuntimeService::_safepoint_time_ticks = NULL;
PerfCounter* RuntimeService::_application_time_ticks = NULL;
jlong RuntimeService::_last_safepoint_sync_time_ns = 0;
jlong RuntimeService::_last_safepoint_end_time_ns = 0;
jlong RuntimeService::_last_app_time_ns = 0;
void RuntimeService::init() {
if (UsePerfData) {
EXCEPTION_MARK;
_sync_time_ticks =
PerfDataManager::create_counter(SUN_RT, "safepointSyncTime",
PerfData::U_Ticks, CHECK);
_total_safepoints =
PerfDataManager::create_counter(SUN_RT, "safepoints",
PerfData::U_Events, CHECK);
_safepoint_time_ticks =
PerfDataManager::create_counter(SUN_RT, "safepointTime",
PerfData::U_Ticks, CHECK);
_application_time_ticks =
PerfDataManager::create_counter(SUN_RT, "applicationTime",
PerfData::U_Ticks, CHECK);
// create performance counters for jvm_version and its capabilities
PerfDataManager::create_constant(SUN_RT, "jvmVersion", PerfData::U_None,
(jlong) VM_Version::jvm_version(), CHECK);
// The capabilities counter is a binary representation of the VM capabilities in string.
// This string respresentation simplifies the implementation of the client side
// to parse the value.
char capabilities[65];
size_t len = sizeof(capabilities);
memset((void*) capabilities, '0', len);
capabilities[len-1] = '\0';
capabilities[0] = AttachListener::is_attach_supported() ? '1' : '0';
#if INCLUDE_SERVICES
capabilities[1] = '1';
#endif // INCLUDE_SERVICES
PerfDataManager::create_string_constant(SUN_RT, "jvmCapabilities",
capabilities, CHECK);
}
}
void RuntimeService::record_safepoint_begin() {
HS_PRIVATE_SAFEPOINT_BEGIN();
// Print the time interval in which the app was executing
if (_app_timer.is_updated()) {
_last_app_time_ns = _app_timer.ticks_since_update();
log_info(safepoint)("Application time: %3.7f seconds", TimeHelper::counter_to_seconds(_last_app_time_ns));
}
// update the time stamp to begin recording safepoint time
_last_safepoint_sync_time_ns = 0;
_last_safepoint_end_time_ns = 0;
_safepoint_timer.update();
if (UsePerfData) {
_total_safepoints->inc();
if (_app_timer.is_updated()) {
_application_time_ticks->inc(_app_timer.ticks_since_update());
}
}
}
void RuntimeService::record_safepoint_synchronized() {
if (UsePerfData) {
_sync_time_ticks->inc(_safepoint_timer.ticks_since_update());
}
if (log_is_enabled(Info, safepoint) || log_is_enabled(Info, safepoint, stats)) {
_last_safepoint_sync_time_ns = _safepoint_timer.ticks_since_update();
}
}
void RuntimeService::record_safepoint_end() {
HS_PRIVATE_SAFEPOINT_END();
// Logging of safepoint+stats=info needs _last_safepoint_end_time_ns to be set.
// Logging of safepoint=info needs _last_safepoint_end_time_ns for following log.
if (log_is_enabled(Info, safepoint) || log_is_enabled(Info, safepoint, stats)) {
_last_safepoint_end_time_ns = _safepoint_timer.ticks_since_update();
log_info(safepoint)(
"Total time for which application threads were stopped: %3.7f seconds, "
"Stopping threads took: %3.7f seconds",
TimeHelper::counter_to_seconds(_last_safepoint_end_time_ns),
TimeHelper::counter_to_seconds(_last_safepoint_sync_time_ns));
}
// update the time stamp to begin recording app time
_app_timer.update();
if (UsePerfData) {
_safepoint_time_ticks->inc(_safepoint_timer.ticks_since_update());
}
}
void RuntimeService::record_safepoint_epilog(const char* operation_name) {
if (!log_is_enabled(Info, safepoint, stats)) {
return;
}
log_info(safepoint, stats)(
"Safepoint \"%s\", "
"Time since last: " JLONG_FORMAT " ns; "
"Reaching safepoint: " JLONG_FORMAT " ns; "
"At safepoint: " JLONG_FORMAT " ns; "
"Total: " JLONG_FORMAT " ns",
operation_name,
_last_app_time_ns,
_last_safepoint_sync_time_ns,
_last_safepoint_end_time_ns - _last_safepoint_sync_time_ns,
_last_safepoint_end_time_ns
);
}
void RuntimeService::record_application_start() {
// update the time stamp to begin recording app time
_app_timer.update();
}
// Don't need to record application end because we currently
// exit at a safepoint and record_safepoint_begin() handles updating
// the application time counter at VM exit.
jlong RuntimeService::safepoint_sync_time_ms() {
return UsePerfData ?
Management::ticks_to_ms(_sync_time_ticks->get_value()) : -1;
}
jlong RuntimeService::safepoint_count() {
return UsePerfData ?
_total_safepoints->get_value() : -1;
}
jlong RuntimeService::safepoint_time_ms() {
return UsePerfData ?
Management::ticks_to_ms(_safepoint_time_ticks->get_value()) : -1;
}
jlong RuntimeService::application_time_ms() {
return UsePerfData ?
Management::ticks_to_ms(_application_time_ticks->get_value()) : -1;
}
#endif // INCLUDE_MANAGEMENT